Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2019	Jul. 15, 2019
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	1-6686
Entity Registrant Name	INTERPUBLIC GROUP OF COMPANIES, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-1024020
Entity Address, Address Description	909 Third Avenue,
Entity Address, City or Town	New York,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10022
Phone Fax Number Description	(212)
Local Phone Number	704-1200
Title of each class	Common Stock, par value $0.10 per share
Trading Symbol	IPG
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000051644
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		387,223,208

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
REVENUE:
Net revenue	$ 2,125.9	$ 1,948.2	$ 4,130.7	$ 3,722.2
Billable expenses	394.3	443.6	750.7	838.7
Total revenue	2,520.2	2,391.8	4,881.4	4,560.9
OPERATING EXPENSES:
Salaries and related expenses	1,381.2	1,292.9	2,802.3	2,623.2
Office and other direct expenses	387.3	333.3	776.5	657.1
Billable expenses	394.3	443.6	750.7	838.7
Cost of services	2,162.8	2,069.8	4,329.5	4,119.0
Selling, general and administrative expenses	18.1	28.8	59.5	63.9
Depreciation and amortization	73.0	44.0	144.1	90.0
Restructuring charges	2.1	0.0	33.9
Total operating expenses	2,256.0	2,142.6	4,567.0	4,272.9
OPERATING INCOME	264.2	249.2	314.4	288.0
EXPENSES AND OTHER INCOME:
Interest expense	(51.6)	(26.1)	(101.4)	(46.0)
Interest income	7.7	4.7	15.5	8.7
Other expense, net	(3.8)	(16.3)	(10.7)	(40.7)
Total (expenses) and other income	(47.7)	(37.7)	(96.6)	(78.0)
Income before income taxes	216.5	211.5	217.8	210.0
Provision for income taxes	43.6	63.6	54.1	76.3
Income of consolidated companies	172.9	147.9	163.7	133.7
Equity in net loss of unconsolidated affiliates	(0.1)	(0.1)	(0.4)	(2.0)
NET INCOME	172.8	147.8	163.3	131.7
Net income attributable to noncontrolling interests	(3.3)	(2.0)	(1.8)	(0.0)
NET INCOME AVAILABLE TO IPG COMMON STOCKHOLDERS	$ 169.5	$ 145.8	$ 161.5	$ 131.7
Earnings per share, Basic	$ 0.44	$ 0.38	$ 0.42	$ 0.34
Earnings per share, Diluted	$ 0.43	$ 0.37	$ 0.41	$ 0.34
Weighted-average number of common shares outstanding, Basic	386.2	383.6	385.4	383.5
Weighted-average number of common shares outstanding, Diluted	391.2	389.5	390.1	388.9

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 172.8	$ 147.8	$ 163.3	$ 131.7
Foreign currency translation:
Foreign currency translation adjustments	4.2	(116.4)	12.5	(94.0)
Reclassification adjustments recognized in net income	4.6	0.9	5.8	13.4
Foreign currency transaction and translation adjustment, net of tax	8.8	(115.5)	18.3	(80.6)
Derivative instruments:
Recognition of previously unrealized losses in net income	0.6	0.6	1.2	1.1
Income tax effect	(0.1)	(0.1)	(0.2)	(0.3)
Net unrecognized gains on derivative instruments, net of tax	0.5	0.5	1.0	0.8
Defined benefit pension and other postretirement plans:
Net actuarial gains (losses) for the period	0.7	(1.4)	0.7	(1.4)
Amortization of unrecognized losses, transition obligation and prior service cost included in net income	1.6	2.0	3.3	3.9
Settlement and curtailment losses included in net income	0.0	0.0	0.0	0.2
Other	0.6	(0.5)	0.3	(0.4)
Income tax effect	(0.1)	0.2	(0.2)	0.1
Defined benefit pension and other postretirement plans adjustment, net of tax	2.8	0.3	4.1	2.4
Other comprehensive income (loss), net of tax	12.1	(114.7)	23.4	(77.4)
TOTAL COMPREHENSIVE INCOME	184.9	33.1	186.7	54.3
Less: comprehensive income (loss) attributable to noncontrolling interests	3.6	(0.1)	2.0	(1.8)
COMPREHENSIVE INCOME ATTRIBUTABLE TO IPG	$ 181.3	$ 33.2	$ 184.7	$ 56.1

Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
ASSETS:
Cash and cash equivalents	$ 614.0	$ 673.4
Accounts receivable, net of allowance of $43.6 and $42.5, respectively	4,389.5	5,126.6
Accounts receivable, billable to clients	1,977.6	1,900.6
Assets held for sale	26.4	5.7
Other current assets	467.9	476.6
Total current assets	7,475.4	8,182.9
Property and equipment, net of accumulated depreciation of $1,103.4 and $1,034.9, respectively	767.1	790.9
Deferred income taxes	297.8	247.0
Goodwill	4,884.1	4,875.9
Other intangible assets	1,052.0	1,094.7
Operating lease right-of-use asset	1,596.5	0.0
Other non-current assets	454.0	428.9
TOTAL ASSETS	16,526.9	15,620.3
LIABILITIES:
Accounts payable	6,022.3	6,698.1
Accrued liabilities	626.4	806.9
Contract liabilities	585.2	533.9
Short-term borrowings	207.1	73.7
Current portion of long-term debt	0.3	0.1
Current portion of operating leases	261.0	0.0
Liabilities held for sale	29.0	11.2
Total current liabilities	7,731.3	8,123.9
Long-term debt	3,563.8	3,660.2
Non-current operating leases	1,463.2	0.0
Deferred compensation	401.6	422.7
Other non-current liabilities	720.3	812.8
TOTAL LIABILITIES	13,880.2	13,019.6
Redeemable noncontrolling interests	188.3	167.9
STOCKHOLDERS' EQUITY:
Common stock	38.6	38.3
Additional paid-in capital	921.4	895.9
Retained earnings	2,381.8	2,400.1
Accumulated other comprehensive loss, net of tax	(917.9)	(941.1)
Total IPG stockholders' equity	2,423.9	2,393.2
Noncontrolling interests	34.5	39.6
TOTAL STOCKHOLDERS' EQUITY	2,458.4	2,432.8
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	16,526.9	15,620.3
Parentheticals:
Allowance for doubtful accounts receivable	43.6	42.5
Accumulated depreciation, property and equipment	$ 1,103.4	$ 1,034.9

Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 163.3	$ 131.7
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	144.1	90.0
Provision for uncollectible receivables	6.7	6.1
Amortization of restricted stock and other non-cash compensation	44.1	46.0
Net amortization of bond discounts and deferred financing costs	4.6	2.7
Deferred income tax provision	(3.0)	(31.0)
Net losses on sales of businesses	11.8	44.2
Other	2.1	1.9
Changes in assets and liabilities, net of acquisitions and divestitures, providing (using) cash:
Accounts receivable	743.3	238.0
Accounts receivable, billable to clients	(75.4)	(233.7)
Other current assets	(62.1)	(124.6)
Accounts payable	(676.9)	(579.3)
Accrued liabilities	(92.2)	(175.9)
Contract liabilities	50.2	38.0
Operating lease right-of-use assets	168.0	(0.0)
Operating lease liabilities	(164.0)	0.0
Other non-current assets and liabilities	(65.6)	(11.8)
Net cash provided by (used in) operating activities	199.0	(557.7)
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(80.1)	(61.5)
Acquisitions, net of cash acquired	(0.6)	(8.5)
Other investing activities	2.8	12.4
Net cash used in investing activities	(77.9)	(57.6)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in short-term borrowings	132.3	669.3
Exercise of stock options	0.6	7.0
Repurchase of common stock	(0.0)	(114.5)
Common stock dividends	(181.4)	(161.2)
Repayment of long-term debt	(100.1)	(4.7)
Tax payments for employee shares withheld	(22.0)	(28.0)
Acquisition-related payments	(13.0)	(16.0)
Distributions to noncontrolling interests	(8.1)	(10.6)
Other financing activities	0.0	(0.3)
Net cash (used in) provided by financing activities	(191.7)	341.0
Effect of foreign exchange rate changes on cash, cash equivalents and restricted cash	10.3	(27.5)
Net decrease in cash, cash equivalents and restricted cash	(60.3)	(301.8)
Cash, cash equivalents, and restricted cash at beginning of period	677.2	797.7
Cash, cash equivalents, and restricted cash at end of period	$ 616.9	$ 495.9

Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock, Shares	Common Stock, Amount	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss, Net of Tax	Treasury Stock	Total IPG Stockholders' Equity	Noncontrolling Interests
Common Stock, Shares, Issued		386.2
Balance at Dec. 31, 2017	$ 2,246.3		$ 38.6	$ 955.2	$ 2,104.5	$ (827.8)	$ (59.0)	$ 2,211.5	$ 34.8
Net income	131.7
Net income available to IPG common stockholders	131.7				131.7			131.7
Net income attributable to noncontrolling interest	0.0								0.0
Other comprehensive income (loss)	(77.4)					(75.6)		(75.6)
Other comprehensive income (loss), attributable to noncontrolling interest									(1.8)
Reclassifications related to redeemable noncontrolling interests	6.3								6.3
Distributions to noncontrolling interests	(10.6)								(10.6)
Change in redemption value of redeemable noncontrolling interests	44.7			41.8	2.9			44.7
Repurchases of common stock	(114.5)						114.5	114.5
Common stock dividends ($0.235 and $0.210 per share, respectively)	(161.2)				(161.2)			(161.2)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		4.6
Stock-based compensation, value	48.5		0.5	48.0				48.5
Exercise of stock options, shares		0.9
Exercise of stock options, value	(7.0)		(0.0)	(7.0)				(7.0)
Shares withheld for taxes, shares		(1.2)
Shares withheld for taxes, value	(28.6)		0.1	28.5				28.6
Other	0.6			0.6	1.2			1.8	(1.2)
Balance at Jun. 30, 2018	2,091.6		39.0	1,022.9	2,076.7	(903.4)	(173.5)	2,061.7	29.9
Common Stock, Shares, Issued		390.3
Balance at Mar. 31, 2018	2,140.3		39.0	963.7	2,010.5	(790.8)	(113.9)	2,108.5	31.8
Net income	147.8
Net income available to IPG common stockholders	145.8				145.8			145.8
Net income attributable to noncontrolling interest	2.0								2.0
Other comprehensive income (loss)	(114.7)					(112.6)		(112.6)
Other comprehensive income (loss), attributable to noncontrolling interest									(2.1)
Reclassifications related to redeemable noncontrolling interests	3.8								3.8
Distributions to noncontrolling interests	(6.7)								(6.7)
Change in redemption value of redeemable noncontrolling interests	43.2			41.8	1.4			43.2
Repurchases of common stock	(59.6)						59.6	59.6
Common stock dividends ($0.235 and $0.210 per share, respectively)	(80.4)				(80.4)			(80.4)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		0.2
Stock-based compensation, value	17.8		0.1	17.7				17.8
Exercise of stock options, shares		0.1
Exercise of stock options, value	(0.0)		(0.1)	(0.1)				(0.0)
Shares withheld for taxes, shares		(0.1)
Shares withheld for taxes, value	(0.5)		(0.0)	0.5				0.5
Other	(0.6)			(0.1)	0.6			0.5	(1.1)
Balance at Jun. 30, 2018	2,091.6		39.0	1,022.9	2,076.7	(903.4)	$ (173.5)	2,061.7	29.9
Common Stock, Shares, Issued		390.5
Common Stock, Shares, Issued		383.6
Balance at Dec. 31, 2018	2,432.8		38.3	895.9	2,400.1	(941.1)		2,393.2	39.6
Cumulative effect of accounting change	2.2				2.2			2.2
Net income	163.3
Net income available to IPG common stockholders	161.5				161.5			161.5
Net income attributable to noncontrolling interest	1.8								1.8
Other comprehensive income (loss)	23.4					23.2		23.2
Other comprehensive income (loss), attributable to noncontrolling interest									0.2
Reclassifications related to redeemable noncontrolling interests	(0.4)								(0.4)
Distributions to noncontrolling interests	(8.1)								(8.1)
Change in redemption value of redeemable noncontrolling interests	1.4				1.4			1.4
Common stock dividends ($0.235 and $0.210 per share, respectively)	(181.4)				(181.4)			(181.4)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		3.6
Stock-based compensation, value	48.5		0.4	48.1				48.5
Exercise of stock options, shares		0.1
Exercise of stock options, value	(0.6)		(0.0)	(0.6)				(0.6)
Shares withheld for taxes, shares		(0.9)
Shares withheld for taxes, value	(22.3)		0.1	22.2				22.3
Other	1.6			1.0	2.0			3.0	(1.4)
Balance at Jun. 30, 2019	2,458.4		38.6	921.4	2,381.8	(917.9)		2,423.9	34.5
Common Stock, Shares, Issued		386.2
Balance at Mar. 31, 2019	2,354.6		38.6	903.3	2,303.1	(929.7)		2,315.3	39.3
Net income	172.8
Net income available to IPG common stockholders	169.5				169.5			169.5
Net income attributable to noncontrolling interest	3.3								3.3
Other comprehensive income (loss)	12.1					11.8		11.8
Other comprehensive income (loss), attributable to noncontrolling interest									0.3
Reclassifications related to redeemable noncontrolling interests	(3.0)								(3.0)
Distributions to noncontrolling interests	(5.6)								(5.6)
Change in redemption value of redeemable noncontrolling interests	1.1				1.1			1.1
Common stock dividends ($0.235 and $0.210 per share, respectively)	(90.8)				(90.8)			(90.8)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		0.2
Stock-based compensation, value	18.4		0.1	18.3				18.4
Exercise of stock options, shares		0.1
Exercise of stock options, value	(0.0)		(0.0)	(0.0)				(0.0)
Shares withheld for taxes, shares		(0.1)
Shares withheld for taxes, value	(0.3)		0.1	0.2				0.3
Other	0.9			(0.0)	1.1			1.1	(0.2)
Balance at Jun. 30, 2019	$ 2,458.4		$ 38.6	$ 921.4	$ 2,381.8	$ (917.9)		$ 2,423.9	$ 34.5
Common Stock, Shares, Issued		386.4

Basis of Presentation (Notes)	6 Months Ended
Basis of Presentation (Notes)	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The unaudited Consolidated Financial Statements have been prepared by The Interpublic Group of Companies, Inc. and its subsidiaries (the "Company," "IPG," "we," "us" or "our") in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") and pursuant to the rules and regulations of the Securities and Exchange Commission (the "SEC") for reporting interim financial information on Form 10-Q. Accordingly, they do not include certain information and disclosures required for complete financial statements. The preparation of financial statements in conformity with U.S. GAAP requires us to make judgments, assumptions and estimates that affect the amounts reported and disclosed. Actual results could differ from these estimates and assumptions. The consolidated results for interim periods are not necessarily indicative of results for the full year and should be read in conjunction with our 2018 Annual Report on Form 10-K. Cost of services is comprised of the expenses of our revenue-producing operating segments, Integrated Agency Networks ("IAN") and Constituency Management Group ("CMG"), including salaries and related expenses, office and other direct expenses and billable expenses, and includes an allocation of the centrally managed expenses of our Corporate and other group. Office and other direct expenses include rent expense, professional fees, certain expenses incurred by our staff in servicing our clients and other costs directly attributable to client engagements. Selling, general and administrative expenses are primarily the unallocated expenses of our Corporate and other group, excluding depreciation and amortization. Depreciation and amortization of fixed assets and intangible assets of the Company is disclosed as a separate operating expense. Restructuring charges relate to the Company's implementation of a cost initiative to better align our cost structure with our revenue, as discussed further in Note 9. In the opinion of management, these unaudited Consolidated Financial Statements include all adjustments, consisting only of normal and recurring adjustments necessary for a fair statement of the information for each period contained therein. Certain reclassifications and immaterial revisions have been made to prior-period financial statements to conform to the current-period presentation.

Revenue (Notes)

6 Months Ended

Jun. 30, 2019

Revenue from Contract with Customer [Abstract]

Revenue

Disaggregation of Revenue

We have two reportable segments as of June 30, 2019: IAN and CMG, as further discussed in Note 13. IAN principally generates revenue from providing advertising and media services as well as a comprehensive array of global communications and marketing services. CMG generates revenue from providing events and public relations services as well as sports and entertainment marketing, corporate and brand identity, and strategic marketing consulting.

Our agencies are located in over 110 countries, including every significant world market. Our geographic revenue breakdown is listed below.



	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	1,595.1	$	1,445.7	$	3,130.2	$	2,796.4
International:
United Kingdom	209.8		201.6		416.0		406.0
Continental Europe	209.4		205.1		388.2		386.8
Asia Pacific	258.2		304.2		490.6		535.7
Latin America	101.8		92.5		191.1		172.5
Other	145.9		142.7		265.3		263.5
Total International	925.1		946.1		1,751.2		1,764.5
Total Consolidated	$	2,520.2	$	2,391.8	$	4,881.4	$	4,560.9



	Three months ended June 30,				Six months ended June 30,
Net revenue:	2019		2018		2019		2018
United States	$	1,337.7	$	1,171.5	$	2,651.8	$	2,263.8
International:
United Kingdom	180.4		175.7		350.7		339.2
Continental Europe	183.3		178.7		340.1		337.4
Asia Pacific	205.1		214.2		383.1		393.0
Latin America	92.1		82.0		172.4		155.9
Other	127.3		126.1		232.6		232.9
Total International	788.2		776.7		1,478.9		1,458.4
Total Consolidated	$	2,125.9	$	1,948.2	$	4,130.7	$	3,722.2



IAN	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	1,215.8	$	1,063.2	$	2,425.9	$	2,086.4
International	752.8		749.3		1,414.9		1,411.6
Total IAN	$	1,968.6	$	1,812.5	$	3,840.8	$	3,498.0

Net revenue:
United States	$	1,131.7	$	963.3	$	2,251.0	$	1,861.3
International	674.1		665.8		1,266.0		1,249.1
Total IAN	$	1,805.8	$	1,629.1	$	3,517.0	$	3,110.4



CMG	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	379.3	$	382.5	$	704.3	$	710.0
International	172.3		196.8		336.3		352.9
Total CMG	$	551.6	$	579.3	$	1,040.6	$	1,062.9

Net revenue:
United States	$	206.0	$	208.2	$	400.8	$	402.5
International	114.1		110.9		212.9		209.3
Total CMG	$	320.1	$	319.1	$	613.7	$	611.8

Contract Balances

The following table provides information about receivables, contract assets and contract liabilities from contracts with customers.



	June 30, 2019		December 31, 2018
Accounts receivable, net of allowance of $43.6 and $42.5, respectively	$	4,389.5	$	5,126.6
Accounts receivable, billable to clients	1,977.6		1,900.6
Contract assets	51.2		67.9
Contract liabilities (deferred revenue)	585.2		533.9

Contract assets are primarily comprised of contract incentives that are generally satisfied annually under the terms of our contracts and are transferred to accounts receivable when the right to payment becomes unconditional. Contract liabilities relate to advance consideration received from customers under the terms of our contracts primarily related to reimbursements of third-party expenses, whether we act as principal or agent, and to a lesser extent, periodic retainer fees, both of which are generally recognized shortly after billing.

The majority of our contracts are for periods of one year or less. For those contracts with a term of more than one year, we had approximately $756.0 of unsatisfied performance obligations as of June 30, 2019, which will be recognized as services are performed over the remaining contractual terms.

Leases (Notes)

6 Months Ended

Jun. 30, 2019

Leases [Abstract]

Lessee, Operating Leases [Text Block]

Leases

Effective January 1, 2019, IPG adopted Accounting Standards Codification Topic 842, Leases ("ASC 842"), using the modified retrospective transition method. As such, we have recognized a right-of-use asset and a corresponding lease liability on our Consolidated Balance Sheet for virtually all of our leases with a term of more than twelve months. Prior-year financial statements were not recast under the new standard and, therefore, those amounts are not presented below. As an accounting policy, we have elected not to apply the recognition requirements to short-term leases, not to separate non-lease components from lease components, and have elected the package of transition provisions available for existing contracts, which allowed us to carry forward our historical assessments of (i) whether contracts are or contain leases, (ii) lease classification and (iii) initial direct costs.

We do not have a material amount of finance leases and the majority of our operating leases, for which we serve as the lessee, consist primarily of real-estate property for our offices around the world. Both the asset and liability are measured at the present value of the future lease payments, with the asset being subject to adjustments such as initial direct costs, prepaid lease payments, and lease incentives. Many of our leases provide for renewal and/or termination options, as well as escalation clauses, which are also factored into our lease payments when appropriate. Our leases have remaining lease terms of 1 year to 20 years. The discount rate used to measure the lease asset and liability is determined at the beginning of the lease term using the rate implicit in the lease, if readily determinable, or using the Company's collateralized credit-adjusted borrowing rate.

The following table presents information on our operating leases for the three and six months ended June 30, 2019.



	Three months ended June 30, 2019			Six months ended June 30, 2019
Operating lease cost	$	81.0		$	159.4
Short-term lease cost	4.9			10.0
Sublease income	(2.7		)	(4.8		)
Total lease cost	$	83.2		$	164.6

				Six months ended June 30, 2019
Cash paid for amounts included in the measurement of lease liabilities				$	164.0
Right-of-use assets obtained in exchange for lease liabilities				$	309.6

				As of June 30, 2019
Weighted-average remaining lease term				Eight years
Weighted-average discount rate				4.36		%

Our future payments of our operating leases as of June 30, 2019 are listed in the table below.



Period	Net Rent
2019	$	174.0
2020	315.3
2021	282.0
2022	250.6
2023	195.2
Thereafter	844.3
Total future lease payments	2,061.4
Less: imputed interest	(337.2		)
Present value of future lease payments	1,724.2
Less: current portion of operating leases	261.0
Non-current operating leases	$	1,463.2

Our future payments of our operating leases as of December 31, 2018 are listed in the table below.



Period	Rent Obligations		Sublease Rental Income			Net Rent
2019	$	352.0	$	(7.7	)	$	344.3
2020	324.3		(5.2		)	319.1
2021	282.3		(2.2		)	280.1
2022	242.5		(1.3		)	241.2
2023	184.0		(0.6		)	183.4
Thereafter	714.6		(0.5		)	714.1
Total future lease payments	$	2,099.7	$	(17.5	)	$	2,082.2

As of June 30, 2019, we have additional operating leases that have not yet commenced with future lease payments of approximately $140.0 that will commence between 2019 and 2020 with lease terms of 5 to 15 years.

Debt and Credit Arrangements (Notes)

6 Months Ended

Jun. 30, 2019

Debt Disclosure [Abstract]

Debt and Credit Arrangements

Long-Term Debt

A summary of the carrying amounts and fair values of our long-term debt is listed below.



	Effective Interest Rate	June 30, 2019				December 31, 2018
	Effective Interest Rate	Book Value		Fair Value ¹		Book Value		Fair Value ¹
3.50% Senior Notes due 2020 (less unamortized discount and issuance costs of $0.6 and $1.8, respectively)	3.89%	$	497.6	$	506.3	$	496.6	$	499.9
3.75% Senior Notes due 2021 (less unamortized discount and issuance costs of $0.3 and $2.4, respectively)	3.98%	497.3		513.6		496.8		503.2
4.00% Senior Notes due 2022 (less unamortized discount and issuance costs of $0.8 and $0.7, respectively)	4.13%	248.5		258.5		248.2		250.3
3.75% Senior Notes due 2023 (less unamortized discount and issuance costs of $0.6 and $1.5, respectively)	4.32%	497.9		520.7		497.7		491.4
4.20% Senior Notes due 2024 (less unamortized discount and issuance costs of $0.5 and $2.0, respectively)	4.24%	497.5		538.2		497.3		492.6
4.65% Senior Notes due 2028 (less unamortized discount and issuance costs of $1.6 and $4.1, respectively)	4.78%	494.3		545.9		494.0		494.1
5.40% Senior Notes due 2048 (less unamortized discount and issuance costs of $2.7 and $5.5, respectively)	5.48%	491.8		555.6		491.7		474.1
Term Loan due 2021 - LIBOR plus 1.25%		300.0		300.0		400.0		400.0
Other notes payable and capitalized leases		39.2		39.2		38.0		38.0
Total long-term debt		3,564.1				3,660.3
Less: current portion		0.3				0.1
Long-term debt, excluding current portion		$	3,563.8			$	3,660.2


1	See Note 14 for information on the fair value measurement of our long-term debt.

Term Loan Agreement

On October 1, 2018, in order to fund the acquisition of Acxiom (the "Acxiom Acquisition"), we entered into financing arrangements with third-party lenders under a three-year term loan agreement (the "Term Loan Agreement"). On June 13, 2019, we repaid $100.0 of the outstanding balance, which reduced our borrowings under the agreement to $300.0. Consistent with our other debt securities, the Term Loan Agreement includes covenants that, among other things, limit our liens and the liens of certain of our consolidated subsidiaries. We were in compliance with all of our covenants in the Term Loan Agreement as of June 30, 2019.

Credit Agreements

We maintain a committed corporate credit facility, originally dated as of July 18, 2008, which has been amended and restated from time to time (the "Credit Agreement"). We use our Credit Agreement to increase our financial flexibility, to provide letters of credit primarily to support obligations of our subsidiaries and to support our commercial paper program. The Credit Agreement is a revolving facility, expiring in October 2022, under which amounts borrowed by us or any of our subsidiaries designated under the Credit Agreement may be repaid and reborrowed, subject to an aggregate lending limit of $1,500.0, or the equivalent in other currencies. The Company has the ability to increase the commitments under the Credit Agreement from time to time by an additional amount of up to $250.0, provided the Company receives commitments for such increases and satisfies certain other conditions. The aggregate available amount of letters of credit outstanding may decrease or increase, subject to a sublimit on letters of credit of $50.0, or the equivalent in other currencies. Our obligations under the Credit Agreement are unsecured. As of June 30, 2019, there were no borrowings under the Credit Agreement; however, we had $8.6 of letters of credit under the Credit Agreement, which reduced our total availability to $1,491.4. We were in compliance with all of our covenants in the Credit Agreement as of June 30, 2019.

We also have uncommitted lines of credit with various banks that permit borrowings at variable interest rates and that are primarily used to fund working capital needs. We have guaranteed the repayment of some of these borrowings made by certain subsidiaries. If we lose access to these credit lines, we would have to provide funding directly to some of our operations. As of June 30, 2019, the Company had uncommitted lines of credit in an aggregate amount of $1,085.5, under which we had outstanding borrowings of $57.1 classified as short-term borrowings on our Consolidated Balance Sheet. The average amount outstanding during the second quarter of 2019 was $98.3, with a weighted-average interest rate of approximately 4.7%.

Commercial Paper

The Company is authorized to issue unsecured commercial paper up to a maximum aggregate amount outstanding at any time of $1,500.0. Borrowings under the program are supported by the Credit Agreement described above. Proceeds of the commercial paper are used for working capital and general corporate purposes, including the repayment of maturing indebtedness and other short-term liquidity needs. The maturities of the commercial paper vary but may not exceed 397 days from the date of issue. As of June 30, 2019, there was $150.0 of commercial paper outstanding classified as short-term borrowings on our Consolidated Balance Sheet. The average amount outstanding under the program during the second quarter of 2019 was $482.6, with a weighted-average interest rate of 2.8% and a weighted-average maturity of 18 days.

Acquisitions (Notes)

6 Months Ended

Jun. 30, 2019

Business Combinations [Abstract]

Acquisitions

Acxiom Acquisition

On October 1, 2018 (the "acquisition date"), the Company completed its acquisition of Acxiom. The purchase accounting process has not been completed primarily because the valuation of acquired assets has not been finalized. We expect to complete the purchase accounting as soon as practicable but no later than one year from the acquisition date. We do not believe there will be material adjustments.

Other Acquisitions

During the first half of 2019, we completed one acquisition, a content communications agency based in the U.K. This acquisition was included in the IAN operating segment. During the first half of 2019, we recorded $2.4 of goodwill and intangible assets related to our acquisitions.

During the first half of 2018, we completed two acquisitions, a full-service digital agency based in Brazil and an entertainment marketing and brand licensing agency in the fashion and lifestyle sector based in the U.K. Both of our acquisitions were included in the CMG operating segment. During the first half of 2018, we recorded $14.2 of goodwill and intangible assets related to our acquisitions.

The results of operations of our acquired companies were included in our consolidated results from the closing date of each acquisition. Details of cash paid for current and prior years' acquisitions are listed below.



	Six months ended June 30,
	2019		2018
Cost of investment: current-year acquisitions	$	0.6	$	8.7
Cost of investment: prior-year acquisitions	13.0		16.2
Less: net cash acquired	—		(0.4		)
Total cost of investment	13.6		24.5
Operating payments ¹	9.1		18.2
Total cash paid for acquisitions ²	$	22.7	$	42.7

Represents cash payments for amounts that have been recognized in operating expenses since the date of acquisition either relating to adjustments to estimates in excess of the initial value of contingent payments recorded or were contingent upon the future employment of the former owners of the acquired companies. Amounts are reflected in the operating section of the unaudited Consolidated Statements of Cash Flows.

Of the total cash paid for acquisitions, $0.6 and $8.5 for the six months ended June 30, 2019 and 2018, respectively, are classified under the investing section of the unaudited Consolidated Statements of Cash Flows, as acquisitions, net of cash acquired. These amounts relate to initial payments for new transactions. Of the total cash paid for acquisitions, $13.0 and $16.0 for the six months ended June 30, 2019 and 2018, respectively, are classified under the financing section of the unaudited Consolidated Statements of Cash Flows as acquisition-related payments. These amounts relate to deferred payments and increases in our ownership interest for prior acquisitions.

Redeemable Noncontrolling Interests

Many of our acquisitions include provisions under which the noncontrolling equity owners may require us to purchase additional interests in a subsidiary at their discretion. Redeemable noncontrolling interests are adjusted quarterly to their estimated redemption value, but not less than their initial fair value. Any adjustments to the redemption value impact retained earnings or additional paid in capital, except for foreign currency translation adjustments.

The following table presents changes in our redeemable noncontrolling interests.



	Six months ended June 30,
	2019			2018
Balance at beginning of period	$	167.9		$	252.1
Change in related noncontrolling interests balance	0.2			(14.6		)
Changes in redemption value of redeemable noncontrolling interests:
Additions	24.3			0.0
Redemptions	(3.1		)	(32.2		)
Redemption value adjustments	(1.0		)	(39.5		)
Balance at end of period	$	188.3		$	165.8

Supplementary Data (Notes)

6 Months Ended

Jun. 30, 2019

Supplementary Data [Abstract]

Accrued Liabilities

The following table presents the components of accrued liabilities.



	June 30, 2019		December 31, 2018
Salaries, benefits and related expenses	$	375.6	$	494.9
Interest	40.2		43.6
Acquisition obligations	38.2		65.7
Office and related expenses	26.2		52.2
Restructuring charges	7.5		0.0
Other	138.7		150.5
Total accrued liabilities	$	626.4	$	806.9

Other Income, Net

Other Expense, Net

Results of operations for the three and six months ended June 30, 2019 and 2018 include certain items that are not directly associated with our revenue-producing operations.



	Three months ended June 30,						Six months ended June 30,
	2019			2018			2019			2018
Net losses on sales of businesses	$	(3.2	)	$	(19.8	)	$	(11.8	)	$	(44.2	)
Other	(0.6		)	3.5			1.1			3.5
Total other expense, net	$	(3.8	)	$	(16.3	)	$	(10.7	)	$	(40.7	)

Net losses on sales of businesses – During the three and six months ended June 30, 2019, the amounts recognized were related to sales of businesses and the classification of certain assets and liabilities, consisting primarily of accounts receivable and cash, as held for sale within our IAN reportable segment. During the three and six months ended June 30, 2018, the amounts recognized were related to sales of businesses and the classification of certain assets and liabilities, consisting primarily of cash, as held for sale within our IAN reportable segment. The businesses held for sale primarily represent unprofitable, non-strategic agencies which are expected to be sold within the next twelve months.

Other – During the three and six months ended June 30, 2019, the amounts recognized were primarily related to a sale of an equity investment.

Share Repurchase Program

On July 2, 2018, in connection with the announcement of the Acxiom Acquisition, we announced that share repurchases will be suspended for a period of time in order to reduce the increased debt levels incurred in conjunction with the acquisition. As of June 30, 2019, $338.4, excluding fees, remains available for repurchase under the share repurchase programs authorized in previous years, which have no expiration date.

Employee Benefits (Notes)

6 Months Ended

Jun. 30, 2019

Defined Benefit Plan [Abstract]

Employee Benefits

We have a defined benefit pension plan that covers certain U.S. employees (the “Domestic Pension Plan”). We also have numerous funded and unfunded plans outside the U.S. The Interpublic Limited Pension Plan in the U.K. is a defined benefit plan and is our most material foreign pension plan in terms of the benefit obligation and plan assets. Some of our domestic and foreign subsidiaries provide postretirement health benefits and life insurance to eligible employees and, in certain cases, their dependents. The domestic postretirement benefit plan is our most material postretirement benefit plan in terms of the benefit obligation. Certain immaterial foreign pension and postretirement benefit plans have been excluded from the table below.

The components of net periodic cost for the Domestic Pension Plan, the significant foreign pension plans and the domestic postretirement benefit plan are listed below.



	Domestic Pension Plan						Foreign Pension Plans						Domestic Postretirement Benefit Plan
Three months ended June 30,	2019			2018			2019			2018			2019			2018
Service cost	$	0.0		$	0.0		$	1.1		$	0.9		$	0.0		$	0.0
Interest cost	1.2			1.1			3.1			3.4			0.3			0.2
Expected return on plan assets	(1.4		)	(1.5		)	(4.4		)	(4.8		)	0.0			0.0
Amortization of:
Prior service cost (credit)	0.0			0.0			0.1			0.1			(0.1		)	(0.1		)
Unrecognized actuarial losses	0.4			0.4			1.2			1.5			0.0			0.1
Net periodic cost	$	0.2		$	0.0		$	1.1		$	1.1		$	0.2		$	0.2



	Domestic Pension Plan						Foreign Pension Plans						Domestic Postretirement Benefit Plan
Six months ended June 30,	2019			2018			2019			2018			2019			2018
Service cost	$	0.0		$	0.0		$	2.3		$	2.0		$	0.0		$	0.0
Interest cost	2.4			2.2			6.3			6.8			0.6			0.5
Expected return on plan assets	(2.9		)	(3.3		)	(8.8		)	(9.7		)	0.0			0.0
Settlements and curtailments	0.0			0.0			0.0			0.2			0.0			0.0
Amortization of:
Prior service cost (credit)	0.0			0.0			0.1			0.1			(0.1		)	(0.1		)
Unrecognized actuarial losses	0.9			0.8			2.4			3.0			0.0			0.1
Net periodic cost	$	0.4		$	(0.3	)	$	2.3		$	2.4		$	0.5		$	0.5

The components of net periodic cost other than the service cost component are included in the line item “Other expense, net” in the Consolidated Statements of Operations.

During the six months ended June 30, 2019, we contributed $1.1 and $8.7 of cash to our domestic and foreign pension plans, respectively. For the remainder of 2019, we expect to contribute approximately $1.0 and $8.0 of cash to our domestic and foreign pension plans, respectively.

Segment Information (Notes)

6 Months Ended

Jun. 30, 2019

Segment Reporting [Abstract]

Segment Reporting Disclosure

Segment Information

As of June 30, 2019, we have two reportable segments: IAN and CMG. IAN is comprised of McCann Worldgroup, Foote, Cone & Belding ("FCB"), MullenLowe Group, IPG Mediabrands, Acxiom, our digital specialist agencies and our domestic integrated agencies. CMG is comprised of a number of our specialist marketing services offerings. We also report results for the “Corporate and other” group. Beginning in the first quarter of 2019, Acxiom's results are presented in IAN although we continue to evaluate our financial reporting structure, and the profitability measure employed by our chief operating decision maker for allocating resources to operating divisions and assessing operating division performance is segment EBITA. Summarized financial information concerning our reportable segments is shown in the following table.



	Three months ended June 30,						Six months ended June 30,
	2019			2018			2019			2018
Total revenue:
IAN	$	1,968.6		$	1,812.5		$	3,840.8		$	3,498.0
CMG	551.6			579.3			1,040.6			1,062.9
Total	$	2,520.2		$	2,391.8		$	4,881.4		$	4,560.9

Net revenue:
IAN	$	1,805.8		$	1,629.1		$	3,517.0		$	3,110.4
CMG	320.1			319.1			613.7			611.8
Total	$	2,125.9		$	1,948.2		$	4,130.7		$	3,722.2

Segment EBITA:
IAN	$	261.7		$	242.2		$	376.2		$	303.2
CMG	43.6			43.2			45.5			63.9
Corporate and other	(19.8		)	(31.0		)	(64.4		)	(68.6		)
Total	$	285.5		$	254.4		$	357.3		$	298.5

Amortization of acquired intangibles:
IAN	$	20.2		$	3.9		$	40.7		$	8.0
CMG	1.1			1.3			2.2			2.5
Corporate and other	0.0			0.0			0.0			0.0
Total	$	21.3		$	5.2		$	42.9		$	10.5

Depreciation:
IAN	$	45.2		$	31.9		$	87.5		$	65.2
CMG	4.9			4.7			9.5			9.6
Corporate and other	1.6			2.2			4.2			4.7
Total	$	51.7		$	38.8		$	101.2		$	79.5

Capital expenditures:
IAN	$	35.9		$	31.9		$	62.4		$	47.7
CMG	2.9			1.9			3.9			3.0
Corporate and other	8.5			4.9			13.8			10.8
Total	$	47.3		$	38.7		$	80.1		$	61.5



	June 30, 2019		December 31, 2018
Total assets ¹:
IAN	$	14,323.1	$	13,867.9
CMG	1,695.1		1,516.7
Corporate and other	508.7		235.7
Total	$	16,526.9	$	15,620.3

1 Results for December 31, 2018 have been restated to conform to the current-period presentation.

The following table presents the reconciliation of segment EBITA to Income before income taxes.



	Three months ended June 30,						Six months ended June 30,
	2019			2018			2019			2018
IAN EBITA	$	261.7		$	242.2		$	376.2		$	303.2
CMG EBITA	43.6			43.2			45.5			63.9
Corporate and other EBITA	(19.8		)	(31.0		)	(64.4		)	(68.6		)
Less: consolidated amortization of acquired intangibles	21.3			5.2			42.9			10.5
Operating income	264.2			249.2			314.4			288.0
Total (expenses) and other income	(47.7		)	(37.7		)	(96.6		)	(78.0		)
Income before income taxes	$	216.5		$	211.5		$	217.8		$	210.0

Fair Value Measurements (Notes)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurements

Authoritative guidance for fair value measurements establishes a fair value hierarchy which requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. There are three levels of inputs that may be used to measure fair value:



Level 1		Unadjusted quoted prices in active markets for identical assets or liabilities. An active market for the asset or liability is a market in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2		Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3		Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Financial Instruments that are Measured at Fair Value on a Recurring Basis

We primarily apply the market approach to determine the fair value of financial instruments that are measured at fair value on a recurring basis. There were no changes to our valuation techniques used to determine the fair value of financial instruments during the six months ended June 30, 2019. The following tables present information about our financial instruments measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018, and indicate the fair value hierarchy of the valuation techniques utilized to determine such fair value.



	June 30, 2019								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total		Balance Sheet Classification
Assets
Cash equivalents	$	260.9	$	0.0	$	0.0	$	260.9	Cash and cash equivalents
Liabilities
Contingent acquisition obligations¹	$	0.0	$	0.0	$	110.6	$	110.6	Accrued liabilities and Other non-current liabilities

	December 31, 2018								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total		Balance Sheet Classification
Assets
Cash equivalents	$	132.1	$	0.0	$	0.0	$	132.1	Cash and cash equivalents
Liabilities
Contingent acquisition obligations ¹	$	0.0	$	0.0	$	148.4	$	148.4	Accrued liabilities and Other non-current liabilities

Contingent acquisition obligations includes deferred acquisition payments and unconditional obligations to purchase additional noncontrolling equity shares of consolidated subsidiaries. Fair value measurement of the obligations is based upon actual and projected operating performance targets as specified in the related agreements. The decrease in this balance of $37.8 from December 31, 2018 to June 30, 2019 is primarily due to payments and a reclassification from an arrangement during the second quarter of 2019. The amounts payable within the next twelve months are classified in accrued liabilities; any amounts payable thereafter are classified in other non-current liabilities.

Financial Instruments that are not Measured at Fair Value on a Recurring Basis

The following table presents information about our financial instruments that are not measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018, and indicates the fair value hierarchy of the valuation techniques utilized to determine such fair value.



	June 30, 2019								December 31, 2018
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Total long-term debt	$	0.0	$	3,738.8	$	39.2	$	3,778.0	$	0.0	$	3,605.6	$	38.0	$	3,643.6

Our long-term debt is comprised of senior notes, a term loan and other notes payable. The fair value of our senior notes, which are traded over-the-counter, is based on quoted prices in markets that are not active. Therefore, these senior notes are classified as Level 2 within the fair value hierarchy. Our term loan is a fixed price commitment that cannot be traded on the open market, and therefore is classified as Level 2 within the fair value hierarchy. Our other notes payable are not actively traded, and their fair value is not solely derived from readily observable inputs. The fair value of our other notes payable is determined based on a discounted cash flow model and other proprietary valuation methods, and therefore is classified as Level 3 within the fair value hierarchy. See Note 4 for further information on our long-term debt.

Non-financial Assets and Liabilities that are Measured at Fair Value on a Nonrecurring Basis

Certain non-financial assets and liabilities are measured at fair value on a nonrecurring basis, primarily goodwill, intangible assets, and property and equipment. Accordingly, these assets are not measured and adjusted to fair value on an ongoing basis but are subject to periodic evaluations for potential impairment.

Recent Accounting Standards (Notes)	6 Months Ended
Recent Accounting Standards (Notes)	Jun. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Standards	Recent Accounting Standards Accounting pronouncements not listed below were assessed and determined to be not applicable or are expected to have minimal impact on our Consolidated Financial Statements. Leases In February 2016, the Financial Accounting Standards Board ("FASB") issued amended guidance on lease accounting. We adopted the standard using the modified retrospective approach with an effective date of January 1, 2019. Prior-year financial statements were not recast under the new standard. The adoption resulted in the presentation of a right-of-use asset and lease liability on our Consolidated Balance Sheet and corresponding impacts on our Consolidated Statement of Cash Flows, but did not have a significant impact on our Consolidated Statements of Operations. See Note 3 for further discussion on our adoption of the new leases standard. Financial Instrument Credit Losses In June 2016, the FASB issued amended guidance on the accounting for credit losses on certain types of financial instruments, including trade receivables. The new model uses a forward-looking expected loss method, as opposed to the incurred loss method in current U.S. GAAP, which will generally result in earlier recognition of allowances for losses. This amended guidance is effective beginning January 1, 2020, with early adoption permitted as early as January 1, 2019. We are currently assessing the impact the adoption of the amended guidance will have on our Consolidated Financial Statements.

Revenue (Tables)

6 Months Ended

Jun. 30, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue Principal Geographic Markets

Our agencies are located in over 110 countries, including every significant world market. Our geographic revenue breakdown is listed below.



	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	1,595.1	$	1,445.7	$	3,130.2	$	2,796.4
International:
United Kingdom	209.8		201.6		416.0		406.0
Continental Europe	209.4		205.1		388.2		386.8
Asia Pacific	258.2		304.2		490.6		535.7
Latin America	101.8		92.5		191.1		172.5
Other	145.9		142.7		265.3		263.5
Total International	925.1		946.1		1,751.2		1,764.5
Total Consolidated	$	2,520.2	$	2,391.8	$	4,881.4	$	4,560.9



	Three months ended June 30,				Six months ended June 30,
Net revenue:	2019		2018		2019		2018
United States	$	1,337.7	$	1,171.5	$	2,651.8	$	2,263.8
International:
United Kingdom	180.4		175.7		350.7		339.2
Continental Europe	183.3		178.7		340.1		337.4
Asia Pacific	205.1		214.2		383.1		393.0
Latin America	92.1		82.0		172.4		155.9
Other	127.3		126.1		232.6		232.9
Total International	788.2		776.7		1,478.9		1,458.4
Total Consolidated	$	2,125.9	$	1,948.2	$	4,130.7	$	3,722.2



IAN	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	1,215.8	$	1,063.2	$	2,425.9	$	2,086.4
International	752.8		749.3		1,414.9		1,411.6
Total IAN	$	1,968.6	$	1,812.5	$	3,840.8	$	3,498.0

Net revenue:
United States	$	1,131.7	$	963.3	$	2,251.0	$	1,861.3
International	674.1		665.8		1,266.0		1,249.1
Total IAN	$	1,805.8	$	1,629.1	$	3,517.0	$	3,110.4



CMG	Three months ended June 30,				Six months ended June 30,
Total revenue:	2019		2018		2019		2018
United States	$	379.3	$	382.5	$	704.3	$	710.0
International	172.3		196.8		336.3		352.9
Total CMG	$	551.6	$	579.3	$	1,040.6	$	1,062.9

Net revenue:
United States	$	206.0	$	208.2	$	400.8	$	402.5
International	114.1		110.9		212.9		209.3
Total CMG	$	320.1	$	319.1	$	613.7	$	611.8

Contract Balances

The following table provides information about receivables, contract assets and contract liabilities from contracts with customers.



	June 30, 2019		December 31, 2018
Accounts receivable, net of allowance of $43.6 and $42.5, respectively	$	4,389.5	$	5,126.6
Accounts receivable, billable to clients	1,977.6		1,900.6
Contract assets	51.2		67.9
Contract liabilities (deferred revenue)	585.2		533.9

Leases (Tables)

6 Months Ended

12 Months Ended

Jun. 30, 2019

Dec. 31, 2018

Leases [Abstract]

Operating Leases

The following table presents information on our operating leases for the three and six months ended June 30, 2019.



	Three months ended June 30, 2019			Six months ended June 30, 2019
Operating lease cost	$	81.0		$	159.4
Short-term lease cost	4.9			10.0
Sublease income	(2.7		)	(4.8		)
Total lease cost	$	83.2		$	164.6

				Six months ended June 30, 2019
Cash paid for amounts included in the measurement of lease liabilities				$	164.0
Right-of-use assets obtained in exchange for lease liabilities				$	309.6

				As of June 30, 2019
Weighted-average remaining lease term				Eight years
Weighted-average discount rate				4.36		%

Schedule of Future Operating Lease Payments

Our future payments of our operating leases as of June 30, 2019 are listed in the table below.



Period	Net Rent
2019	$	174.0
2020	315.3
2021	282.0
2022	250.6
2023	195.2
Thereafter	844.3
Total future lease payments	2,061.4
Less: imputed interest	(337.2		)
Present value of future lease payments	1,724.2
Less: current portion of operating leases	261.0
Non-current operating leases	$	1,463.2

Our future payments of our operating leases as of December 31, 2018 are listed in the table below.



Period	Rent Obligations		Sublease Rental Income			Net Rent
2019	$	352.0	$	(7.7	)	$	344.3
2020	324.3		(5.2		)	319.1
2021	282.3		(2.2		)	280.1
2022	242.5		(1.3		)	241.2
2023	184.0		(0.6		)	183.4
Thereafter	714.6		(0.5		)	714.1
Total future lease payments	$	2,099.7	$	(17.5	)	$	2,082.2

Debt and Credit Arrangements (Tables)

6 Months Ended

Jun. 30, 2019

Debt Disclosure [Abstract]

Summary of Carrying Amounts and Fair Values of Long-term Debt

A summary of the carrying amounts and fair values of our long-term debt is listed below.



	Effective Interest Rate	June 30, 2019				December 31, 2018
	Effective Interest Rate	Book Value		Fair Value ¹		Book Value		Fair Value ¹
3.50% Senior Notes due 2020 (less unamortized discount and issuance costs of $0.6 and $1.8, respectively)	3.89%	$	497.6	$	506.3	$	496.6	$	499.9
3.75% Senior Notes due 2021 (less unamortized discount and issuance costs of $0.3 and $2.4, respectively)	3.98%	497.3		513.6		496.8		503.2
4.00% Senior Notes due 2022 (less unamortized discount and issuance costs of $0.8 and $0.7, respectively)	4.13%	248.5		258.5		248.2		250.3
3.75% Senior Notes due 2023 (less unamortized discount and issuance costs of $0.6 and $1.5, respectively)	4.32%	497.9		520.7		497.7		491.4
4.20% Senior Notes due 2024 (less unamortized discount and issuance costs of $0.5 and $2.0, respectively)	4.24%	497.5		538.2		497.3		492.6
4.65% Senior Notes due 2028 (less unamortized discount and issuance costs of $1.6 and $4.1, respectively)	4.78%	494.3		545.9		494.0		494.1
5.40% Senior Notes due 2048 (less unamortized discount and issuance costs of $2.7 and $5.5, respectively)	5.48%	491.8		555.6		491.7		474.1
Term Loan due 2021 - LIBOR plus 1.25%		300.0		300.0		400.0		400.0
Other notes payable and capitalized leases		39.2		39.2		38.0		38.0
Total long-term debt		3,564.1				3,660.3
Less: current portion		0.3				0.1
Long-term debt, excluding current portion		$	3,563.8			$	3,660.2

See Note 14 for information on the fair value measurement of our long-term debt.

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Acquisitions Acquisitions (Tables)

6 Months Ended

Jun. 30, 2019

Business Combinations [Abstract]

Cash paid for acquisitions

Details of cash paid for current and prior years' acquisitions are listed below.



	Six months ended June 30,
	2019		2018
Cost of investment: current-year acquisitions	$	0.6	$	8.7
Cost of investment: prior-year acquisitions	13.0		16.2
Less: net cash acquired	—		(0.4		)
Total cost of investment	13.6		24.5
Operating payments ¹	9.1		18.2
Total cash paid for acquisitions ²	$	22.7	$	42.7

Redeemable Noncontrolling Interest [Table Text Block]

The following table presents changes in our redeemable noncontrolling interests.



	Six months ended June 30,
	2019			2018
Balance at beginning of period	$	167.9		$	252.1
Change in related noncontrolling interests balance	0.2			(14.6		)
Changes in redemption value of redeemable noncontrolling interests:
Additions	24.3			0.0
Redemptions	(3.1		)	(32.2		)
Redemption value adjustments	(1.0		)	(39.5		)
Balance at end of period	$	188.3		$	165.8

Accumulated Other Comprehensive Loss, Net of Tax (Tables)

6 Months Ended

Jun. 30, 2019

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss)

Accumulated Other Comprehensive Loss, Net of Tax

The following tables present the changes in accumulated other comprehensive loss, net of tax, by component.



	Foreign Currency Translation Adjustments			Derivative Instruments			Defined Benefit Pension and Other Postretirement Plans			Total
Balance as of December 31, 2018	$	(716.4	)	$	(5.3	)	$	(219.4	)	$	(941.1	)
Other comprehensive income before reclassifications	12.3			0.0			1.5			13.8
Amount reclassified from accumulated other comprehensive loss, net of tax	5.8			1.0			2.6			9.4
Balance as of June 30, 2019	$	(698.3	)	$	(4.3	)	$	(215.3	)	$	(917.9	)



	Foreign Currency Translation Adjustments			Derivative Instruments			Defined Benefit Pension and Other Postretirement Plans			Total
Balance as of December 31, 2017	$	(585.3	)	$	(6.8	)	$	(235.7	)	$	(827.8	)
Other comprehensive loss before reclassifications	(92.2		)	0.0			(0.9		)	(93.1		)
Amount reclassified from accumulated other comprehensive loss, net of tax	13.4			0.8			3.3			17.5
Balance as of June 30, 2018	$	(664.1	)	$	(6.0	)	$	(233.3	)	$	(903.4	)

Reclassification out of Accumulated Other Comprehensive Income

Amounts reclassified from accumulated other comprehensive loss, net of tax, for the three and six months ended June 30, 2019 and 2018 are as follows:



	Three months ended June 30,						Six months ended June 30,						Affected Line Item in the Consolidated Statements of Operations
	2019			2018			2019			2018
Foreign currency translation adjustments	$	4.6		$	0.9		$	5.8		$	13.4		Other expense, net
Losses on derivative instruments	0.6			0.6			1.2			1.1			Interest expense
Amortization of defined benefit pension and postretirement plan items	1.6			2.0			3.3			4.1			Other expense, net
Tax effect	(0.4		)	(0.5		)	(0.9		)	(1.1		)	Provision for income taxes
Total amount reclassified from accumulated other comprehensive loss, net of tax	$	6.4		$	3.0		$	9.4		$	17.5

Segment Information (Tables)

6 Months Ended

Jun. 30, 2019

Segment Reporting [Abstract]

Summarized financial information concerning reportable segments

Summarized financial information concerning our reportable segments is shown in the following table.



	Three months ended June 30,						Six months ended June 30,
	2019			2018			2019			2018
Total revenue:
IAN	$	1,968.6		$	1,812.5		$	3,840.8		$	3,498.0
CMG	551.6			579.3			1,040.6			1,062.9
Total	$	2,520.2		$	2,391.8		$	4,881.4		$	4,560.9

Net revenue:
IAN	$	1,805.8		$	1,629.1		$	3,517.0		$	3,110.4
CMG	320.1			319.1			613.7			611.8
Total	$	2,125.9		$	1,948.2		$	4,130.7		$	3,722.2

Segment EBITA:
IAN	$	261.7		$	242.2		$	376.2		$	303.2
CMG	43.6			43.2			45.5			63.9
Corporate and other	(19.8		)	(31.0		)	(64.4		)	(68.6		)
Total	$	285.5		$	254.4		$	357.3		$	298.5

Amortization of acquired intangibles:
IAN	$	20.2		$	3.9		$	40.7		$	8.0
CMG	1.1			1.3			2.2			2.5
Corporate and other	0.0			0.0			0.0			0.0
Total	$	21.3		$	5.2		$	42.9		$	10.5

Depreciation:
IAN	$	45.2		$	31.9		$	87.5		$	65.2
CMG	4.9			4.7			9.5			9.6
Corporate and other	1.6			2.2			4.2			4.7
Total	$	51.7		$	38.8		$	101.2		$	79.5

Capital expenditures:
IAN	$	35.9		$	31.9		$	62.4		$	47.7
CMG	2.9			1.9			3.9			3.0
Corporate and other	8.5			4.9			13.8			10.8
Total	$	47.3		$	38.7		$	80.1		$	61.5



	June 30, 2019		December 31, 2018
Total assets ¹:
IAN	$	14,323.1	$	13,867.9
CMG	1,695.1		1,516.7
Corporate and other	508.7		235.7
Total	$	16,526.9	$	15,620.3

1 Results for December 31, 2018 have been restated to conform to the current-period presentation.

The following table presents the reconciliation of segment EBITA to Income before income taxes.



	Three months ended June 30,						Six months ended June 30,
	2019			2018			2019			2018
IAN EBITA	$	261.7		$	242.2		$	376.2		$	303.2
CMG EBITA	43.6			43.2			45.5			63.9
Corporate and other EBITA	(19.8		)	(31.0		)	(64.4		)	(68.6		)
Less: consolidated amortization of acquired intangibles	21.3			5.2			42.9			10.5
Operating income	264.2			249.2			314.4			288.0
Total (expenses) and other income	(47.7		)	(37.7		)	(96.6		)	(78.0		)
Income before income taxes	$	216.5		$	211.5		$	217.8		$	210.0

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Fair Value, Assets and Liabilities Measured on Recurring Basis

The following tables present information about our financial instruments measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018, and indicate the fair value hierarchy of the valuation techniques utilized to determine such fair value.



	June 30, 2019								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total		Balance Sheet Classification
Assets
Cash equivalents	$	260.9	$	0.0	$	0.0	$	260.9	Cash and cash equivalents
Liabilities
Contingent acquisition obligations¹	$	0.0	$	0.0	$	110.6	$	110.6	Accrued liabilities and Other non-current liabilities

	December 31, 2018								Balance Sheet Classification
	Level 1		Level 2		Level 3		Total		Balance Sheet Classification
Assets
Cash equivalents	$	132.1	$	0.0	$	0.0	$	132.1	Cash and cash equivalents
Liabilities
Contingent acquisition obligations ¹	$	0.0	$	0.0	$	148.4	$	148.4	Accrued liabilities and Other non-current liabilities

Fair Value, Assets and Liabilities Measured on Nonrecurring Basis



	June 30, 2019								December 31, 2018
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Total long-term debt	$	0.0	$	3,738.8	$	39.2	$	3,778.0	$	0.0	$	3,605.6	$	38.0	$	3,643.6

Revenue Major Geographical Area (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total revenues:
Total revenue	$ 2,520.2	$ 2,391.8	$ 4,881.4	$ 4,560.9
Net revenue	2,125.9	1,948.2	4,130.7	3,722.2
United States
Total revenues:
Total revenue	1,595.1	1,445.7	3,130.2	2,796.4
Net revenue	1,337.7	1,171.5	2,651.8	2,263.8
United Kingdom
Total revenues:
Total revenue	209.8	201.6	416.0	406.0
Net revenue	180.4	175.7	350.7	339.2
Continental Europe
Total revenues:
Total revenue	209.4	205.1	388.2	386.8
Net revenue	183.3	178.7	340.1	337.4
Asia Pacific
Total revenues:
Total revenue	258.2	304.2	490.6	535.7
Net revenue	205.1	214.2	383.1	393.0
Latin America
Total revenues:
Total revenue	101.8	92.5	191.1	172.5
Net revenue	92.1	82.0	172.4	155.9
Other
Total revenues:
Total revenue	145.9	142.7	265.3	263.5
Net revenue	127.3	126.1	232.6	232.9
International
Total revenues:
Total revenue	925.1	946.1	1,751.2	1,764.5
Net revenue	788.2	776.7	1,478.9	1,458.4
IAN
Total revenues:
Total revenue	1,968.6	1,812.5	3,840.8	3,498.0
Net revenue	1,805.8	1,629.1	3,517.0	3,110.4
IAN \| United States
Total revenues:
Total revenue	1,215.8	1,063.2	2,425.9	2,086.4
Net revenue	1,131.7	963.3	2,251.0	1,861.3
IAN \| International
Total revenues:
Total revenue	752.8	749.3	1,414.9	1,411.6
Net revenue	674.1	665.8	1,266.0	1,249.1
CMG
Total revenues:
Total revenue	551.6	579.3	1,040.6	1,062.9
Net revenue	320.1	319.1	613.7	611.8
CMG \| United States
Total revenues:
Total revenue	379.3	382.5	704.3	710.0
Net revenue	206.0	208.2	400.8	402.5
CMG \| International
Total revenues:
Total revenue	172.3	196.8	336.3	352.9
Net revenue	$ 114.1	$ 110.9	$ 212.9	$ 209.3

Revenue Contract Balances (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Accounts receivable, net of allowance of $43.6 and $42.5, respectively	$ 4,389.5	$ 5,126.6
Accounts receivable, billable to clients	1,977.6	1,900.6
Contract assets	51.2	67.9
Contract liabilities (deferred revenue)	585.2	$ 533.9
Revenue, Remaining Performance Obligation, Amount	$ 756.0

Leases (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Leases (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Minimum Remaining Lease Term		1 year
Remaining lease terms		20 years
Lessee, Operating Lease, Description [Abstract]
Operating lease cost	$ 81.0	$ 159.4
Short-term lease cost	4.9	10.0
Sublease income	2.7	4.8
Total lease cost	$ 83.2	164.6
Cash paid for amounts included in the measurement of lease liabilities		164.0
Right-of-use assets obtained in exchange for lease liabilities		$ 309.6
Weighted-average remaining lease term	8 years	8 years
Weighted-average discount rate	4.36%	4.36%
Future Lease Payments [Abstract]
2019	$ 174.0	$ 174.0
2020	315.3	315.3
2021	282.0	282.0
2022	250.6	250.6
2023	195.2	195.2
Thereafter	844.3	844.3
Total future lease payments	2,061.4	2,061.4
Less: imputed interest	337.2	337.2
Present value of future lease payments	1,724.2	1,724.2
Less: current portion of operating leases	261.0	261.0	$ 0.0
Non-current operating leases	1,463.2	1,463.2	0.0
Future Lease Payments as of Prior Year End [Abstract]
Rent Obligations 2019			352.0
Sublease Rental Income 2019			7.7
Net Rent 2019			344.3
Rent Obligations 2020			324.3
Sublease Rental Income 2020			5.2
Net Rent 2020			319.1
Rent Obligations 2021			282.3
Sublease Rental Income 2021			2.2
Net Rent 2021			280.1
Rent Obligations 2022			242.5
Sublease Rental Income 2022			1.3
Net Rent 2022			241.2
Rent Obligations 2023			184.0
Sublease Rental Income 2023			0.6
Net Rent 2023			183.4
Rent Obligations Thereafter			714.6
Sublease Rental Income Thereafter			0.5
Net Rent Thereafter			714.1
Rent Obligations			2,099.7
Sublease Rental Income			17.5
Net Rent			$ 2,082.2
Lessee, Operating Lease, Not yet Commenced, Description [Abstract]
Future lease payments for additional operating leases that have not yet commenced	$ 140.0	$ 140.0
Minimum Lease Term for Leases That Have Not Yet Commenced		5 years
Maximum Lease Term for Leases That Have Not Yet Commenced		15 years

Long-term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 3,564.1	$ 3,660.3
Long-term Debt, Current Maturities	0.3	0.1
Long-term Debt, Excluding Current Maturities	3,563.8	3,660.2
3.50% Notes Due 2020 (less unamortized discount and issuance costs of $0.6 and $1.8, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2020
Interest Rate Stated Percentage	3.50%
Effective Interest Rate	3.89%
Unamortized Discount	$ 0.6
Issuance Cost	1.8
Long-term Debt, Gross	497.6	496.6
Long-term Debt, Fair Value	$ 506.3	499.9
3.75% Notes Due 2021 (less unamortized discount and issuance costs of $0.3 and $2.4, respectively)
Debt Instrument [Line Items]
Maturity Date	Oct. 01, 2021
Interest Rate Stated Percentage	3.75%
Effective Interest Rate	3.98%
Unamortized Discount	$ 0.3
Issuance Cost	2.4
Long-term Debt, Gross	497.3	496.8
Long-term Debt, Fair Value	513.6	503.2
4.00% Notes Due 2022 (less unamortized discount and issuance costs of $0.8 and $0.7, respectively)
Debt Instrument [Line Items]
Par Value	$ 250.0
Maturity Date	Mar. 15, 2022
Interest Rate Stated Percentage	4.00%
Effective Interest Rate	4.13%
Unamortized Discount	$ 0.8
Issuance Cost	0.7
Long-term Debt, Gross	248.5	248.2
Long-term Debt, Fair Value	258.5	250.3
3.75% Notes Due 2023 (less unamortized discount and issuance costs of $0.6 and $1.5, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Feb. 15, 2023
Interest Rate Stated Percentage	3.75%
Effective Interest Rate	4.32%
Unamortized Discount	$ 0.6
Issuance Cost	1.5
Long-term Debt, Gross	497.9	497.7
Long-term Debt, Fair Value	520.7	491.4
4.20% Notes Due 2024 (less unamortized discount and issuance costs of $0.5 and $2.0, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Apr. 15, 2024
Interest Rate Stated Percentage	4.20%
Effective Interest Rate	4.24%
Unamortized Discount	$ 0.5
Issuance Cost	2.0
Long-term Debt, Gross	497.5	497.3
Long-term Debt, Fair Value	538.2	492.6
4.65% Notes Due 2028 (less unamortized discount and issuance costs of $1.6 and $4.1, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2028
Interest Rate Stated Percentage	4.65%
Effective Interest Rate	4.78%
Unamortized Discount	$ 1.6
Issuance Cost	4.1
Long-term Debt, Gross	494.3	494.0
Long-term Debt, Fair Value	545.9	494.1
5.40% Notes Due 2048 (less unamortized discount and issuance costs of $2.7 and $5.5, respectively)
Debt Instrument [Line Items]
Par Value	$ 500.0
Maturity Date	Oct. 01, 2048
Interest Rate Stated Percentage	5.40%
Effective Interest Rate	5.48%
Unamortized Discount	$ 2.7
Issuance Cost	5.5
Long-term Debt, Gross	491.8	491.7
Long-term Debt, Fair Value	555.6	474.1
Term Loan due 2021 - LIBOR plus 1.25%
Debt Instrument [Line Items]
Long-term Debt, Gross	300.0	400.0
Long-term Debt	300.0
Other notes payable and capitalized leases
Debt Instrument [Line Items]
Long-term Debt, Gross	39.2	38.0
Long-term Debt, Fair Value	$ 39.2	$ 38.0

Credit Facilities (Details) $ in Millions	6 Months Ended
Credit Facilities (Details) $ in Millions	Jun. 30, 2019 USD ($)
Committed credit facility [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,500.0
Line of Credit Facility, Available Capacity Increase Amount	250.0
Line of Credit Facility, Limit on Letters of Credit	50.0
Line of Credit Outstanding, Amount	0.0
Letters of Credit Outstanding, Amount	8.6
Line of Credit Facility, Remaining Borrowing Capacity	1,491.4
Uncommitted credit facility [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	1,085.5
Line of Credit Outstanding, Amount	57.1
Line of Credit Facility, Average Outstanding Amount	$ 98.3
Short-term Debt, Weighted Average Interest Rate, over Time	4.70%

Commercial Paper (Details) $ in Millions	6 Months Ended
Commercial Paper (Details) $ in Millions	Jun. 30, 2019 USD ($)
Debt Disclosure [Abstract]
Commercial paper borrowing capacity	$ 1,500.0
Debt Instrument, Term	397 days
Commercial Paper	$ 150.0
Average amount borrowed under commercial paper during the period	$ 482.6
Commercial paper weighted average interest rate over time	2.80%
Commercial paper weighted-average maturity days outstanding	18 days

Acquisitions Cash Paid for Acquisitions (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash Paid for Acquisitions [Abstract]
Cost of investment: current-year acquisitions	$ 0.6	$ 8.7
Cost of investment: prior-year acquisitions	13.0	16.2
Less: net cash acquired	0.0	(0.4)
Total cost of investment	13.6	24.5
Operating payments	9.1	18.2
Total cash paid for acquisitions	$ 22.7	$ 42.7

Acquisitions Redeemable Noncontrolling Interests (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Redeemable Noncontrolling Interests
Balance at beginning of period	$ 167.9	$ 252.1
Change in related noncontrolling interests balance	0.2	(14.6)
Changes in redemption value of redeemable noncontrolling interests:
Additions	24.3	0.0
Redemptions	(3.1)	(32.2)
Redemption value adjustments	(1.0)	(39.5)
Balance at end of period	$ 188.3	$ 165.8

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Net income available to IPG common stockholders	$ 169.5	$ 145.8	$ 161.5	$ 131.7
Weighted-average number of common shares outstanding, Basic	386.2	383.6	385.4	383.5
Dilutive effect of stock options and restricted shares	5.0	5.9	4.7	5.4
Weighted-average number of common shares outstanding, Diluted	391.2	389.5	390.1	388.9
Loss per share, Basic	$ 0.44	$ 0.38	$ 0.42	$ 0.34
Loss per share, Diluted	$ 0.43	$ 0.37	$ 0.41	$ 0.34

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Supplementary Data Accrued Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Accrued Liabilities [Abstract]
Salaries, benefits and related expenses	$ 375.6	$ 494.9
Acquisition obligations	38.2	65.7
Interest	40.2	43.6
Office and related expenses	26.2	52.2
Restructuring charges	7.5	0.0
Other	138.7	150.5
Total accrued liabilities	$ 626.4	$ 806.9

Restructuring Charges (Details) $ in Millions	3 Months Ended		6 Months Ended
Restructuring Charges (Details) $ in Millions	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Restructuring and Related Cost, Number of Positions Eliminated			627
Severance and termination costs	$ 2.1		$ 22.0
Lease impairment cost	0.0		11.9
Restructuring charges	2.1	$ 0.0	33.9
Payments for Restructuring			(14.5)
Restructuring Reserve	$ 7.5		7.5	$ 0.0
IAN [Member]
Restructuring charges			27.6
CMG [Member]
Restructuring charges			$ 5.6

Incentive Compensation Plans Stock-based Compensation Awards (Details) shares in Millions	6 Months Ended
	Jun. 30, 2019 $ / shares shares
Restricted stock (shares or units)
Incentive Compensation Plans
Granted awards	2.4
Weighted average grant date fair value \| $ / shares	$ 22.84
Performance-based stock (shares)
Incentive Compensation Plans
Granted awards	2.1
Weighted average grant date fair value \| $ / shares	$ 20.16
Total stock-based compensation awards
Incentive Compensation Plans
Granted awards	4.5

Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
AOCI, Debt Securities, Available-for-sale, Adjustment, after Tax	$ (4.3)	$ (6.0)	$ (5.3)	$ (6.8)
Foreign currency translation adjustment:
Balance at beginning of period	(716.4)	(585.3)
Other comprehensive income before reclassifications	12.3	(92.2)
Amount reclassified from accumulated other comprehensive loss, net of tax	5.8	13.4
Balance at end of period	(698.3)	(664.1)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	1.0	0.8
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Reclassification Adjustments and Tax	0.0	0.0
Derivative instruments:
Balance at beginning of period	(219.4)	(235.7)
Other comprehensive income before reclassifications	1.5	(0.9)
Amount reclassified from accumulated other comprehensive loss, net of tax	2.6	3.3
Balance at end of period	(215.3)	(233.3)
Total:
Balance at beginning of period	(941.1)	(827.8)
Other comprehensive income before reclassifications	13.8	(93.1)
Amount reclassified from accumulated other comprehensive loss, net of tax	9.4	17.5
Balance at end of period	$ (917.9)	$ (903.4)

Accumulated Other Comprehensive Loss, Net of Tax Reclassification of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments	$ 4.6	$ 0.9	$ 5.8	$ 13.4
Losses on derivative instruments	0.6	0.6	1.2	1.1
Amortization of defined benefit pension and postretirement plans items	1.6	2.0	3.3	4.1
Tax effect	(0.4)	(0.5)	(0.9)	(1.1)
Reclassifications from accumulated other comprehensive loss to earnings, net of tax	$ 6.4	$ 3.0	$ 9.4	$ 17.5

Employee Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Employee Benefits (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Defined Pension and Postretirement Benefit Plans
Document Period End Date			Jun. 30, 2019
Domestic Plan [Member]
Defined Pension and Postretirement Benefit Plans
Service cost	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Interest cost	1.2	1.1	2.4	2.2
Expected return on plan assets	(1.4)	(1.5)	(2.9)	(3.3)
Settlement and curtailments			(0.0)	(0.0)
Amortization of:
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0.0	0.0	0.0	0.0
Unrecognized actuarial losses	0.4	0.4	0.9	0.8
Net periodic cost	0.2	0.0	0.4	(0.3)
Pension plan - employer contributions			1.1
Pension plan - estimated employer contributions for remainder of current fiscal year	1.0		1.0
Foreign Plan [Member]
Defined Pension and Postretirement Benefit Plans
Service cost	1.1	0.9	2.3	2.0
Interest cost	3.1	3.4	6.3	6.8
Expected return on plan assets	(4.4)	(4.8)	(8.8)	(9.7)
Settlement and curtailments			(0.0)	0.2
Amortization of:
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0.1	0.1	0.1	0.1
Unrecognized actuarial losses	1.2	1.5	2.4	3.0
Net periodic cost	1.1	1.1	2.3	2.4
Pension plan - employer contributions			8.7
Pension plan - estimated employer contributions for remainder of current fiscal year	8.0		8.0
Domestic Postretirement Benefit Plan
Defined Pension and Postretirement Benefit Plans
Service cost	0.0	0.0	0.0	0.0
Interest cost	0.3	0.2	0.6	0.5
Expected return on plan assets	(0.0)	(0.0)	(0.0)	(0.0)
Settlement and curtailments			(0.0)	(0.0)
Amortization of:
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(0.1)	(0.1)	(0.1)	(0.1)
Unrecognized actuarial losses	(0.0)	0.1	(0.0)	0.1
Net periodic cost	$ 0.2	$ 0.2	$ 0.5	$ 0.5

Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Segment Information (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Segments:
Net revenue	$ 2,125.9	$ 1,948.2	$ 4,130.7	$ 3,722.2
Document Period End Date			Jun. 30, 2019
Total revenue	2,520.2	2,391.8	$ 4,881.4	4,560.9
EBITA	285.5	254.4	357.3	298.5
Amortization	(21.3)	(5.2)	(42.9)	(10.5)
Depreciation	51.7	38.8	101.2	79.5
Capital expenditures	47.3	38.7	80.1	61.5
Total assets	16,526.9		16,526.9		$ 15,620.3
Operating income	264.2	249.2	314.4	288.0
Total (expenses) and other income	(47.7)	(37.7)	(96.6)	(78.0)
Income (loss) before income taxes	216.5	211.5	217.8	210.0
IAN
Segments:
Net revenue	1,805.8	1,629.1	3,517.0	3,110.4
Total revenue	1,968.6	1,812.5	3,840.8	3,498.0
EBITA	261.7	242.2	376.2	303.2
Amortization	(20.2)	(3.9)	(40.7)	(8.0)
Depreciation	45.2	31.9	87.5	65.2
Capital expenditures	35.9	31.9	62.4	47.7
Total assets	14,323.1		14,323.1		13,867.9
CMG
Segments:
Net revenue	320.1	319.1	613.7	611.8
Total revenue	551.6	579.3	1,040.6	1,062.9
EBITA	43.6	43.2	45.5	63.9
Amortization	(1.1)	(1.3)	(2.2)	(2.5)
Depreciation	4.9	4.7	9.5	9.6
Capital expenditures	2.9	1.9	3.9	3.0
Total assets	1,695.1		1,695.1		1,516.7
Corporate and Other
Segments:
EBITA	(19.8)	(31.0)	(64.4)	(68.6)
Amortization	(0.0)	(0.0)	(0.0)	(0.0)
Depreciation	1.6	2.2	4.2	4.7
Capital expenditures	8.5	$ 4.9	13.8	$ 10.8
Total assets	$ 508.7		$ 508.7		$ 235.7

Fair Value on a Recurring Basis (Details) - USD ($)
$ in Millions

6 Months Ended

Jun. 30, 2019

Dec. 31, 2018

Fair value assets and liabilities measured on recurring basis

Contingent acquisition liability, total change

$ (37.8)

Level 1

Fair value assets and liabilities measured on recurring basis

Cash equivalents

260.9

$ 132.1

Contingent acquisition obligations

^[1]

0.0

Level 2

Fair value assets and liabilities measured on recurring basis

Cash equivalents

0.0

Contingent acquisition obligations

^[1]

0.0

Level 3

Fair value assets and liabilities measured on recurring basis

Cash equivalents

0.0

Contingent acquisition obligations

^[1]

110.6

148.4

Fair Value, Total [Member]

Fair value assets and liabilities measured on recurring basis

Cash equivalents

260.9

132.1

Contingent acquisition obligations

^[1]

$ 110.6

$ 148.4

[1]

Income Taxes (Notes)	6 Months Ended
Income Taxes (Notes)	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the three and six months ended June 30, 2019, our income tax provision was positively impacted by the settlement of state income tax audits, partially offset by losses in certain foreign jurisdictions where we receive no tax benefit due to 100% valuation allowances, and net losses on sales of businesses and the classification of certain assets as held for sale, for which we did not receive a tax benefit. We have various tax years under examination by tax authorities in various countries, and in various states, in which we have significant business operations. It is not yet known whether these examinations will, in the aggregate, result in our paying additional taxes. We believe our tax reserves are adequate in relation to the potential for additional assessments in each of the jurisdictions in which we are subject to taxation. We regularly assess the likelihood of additional tax assessments in those jurisdictions and, if necessary, adjust our reserves as additional information or events require. With respect to all tax years open to examination by U.S. federal, various state and local, and non-U.S. tax authorities, we currently anticipate that total unrecognized tax benefits will decrease by an amount between $10.0 and $20.0 in the next twelve months, a portion of which will affect our effective income tax rate, primarily as a result of the settlement of tax examinations and the lapsing of statutes of limitations. We are effectively settled with respect to U.S. federal income tax audits through 2012, with the exception of 2009. With limited exceptions, we are no longer subject to state and local income tax audits for years prior to 2013 or non-U.S. income tax audits for years prior to 2009.

Commitments and Contingencies (Notes)	6 Months Ended
Commitments and Contingencies (Notes)	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Matters We are involved in various legal proceedings, and subject to investigations, inspections, audits, inquiries and similar actions by governmental authorities, arising in the normal course of business. The types of allegations that arise in connection with such legal proceedings may vary in nature, but can include claims related to contract, employment, tax and intellectual property matters. We evaluate all cases each reporting period and record liabilities for losses from legal proceedings when we determine that it is probable that the outcome in a legal proceeding will be unfavorable and the amount, or potential range, of loss can be reasonably estimated. In certain cases, we cannot reasonably estimate the potential loss because, for example, the litigation is in its early stages. While any outcome related to litigation or such governmental proceedings in which we are involved cannot be predicted with certainty, management believes that the outcome of these matters, individually and in the aggregate, will not have a material adverse effect on our financial condition, results of operations or cash flows. Guarantees As discussed in our 2018 Annual Report on Form 10-K, we have guaranteed certain obligations of our subsidiaries relating principally to operating leases, uncommitted lines of credit and cash pooling arrangements. As of June 30, 2019 and December 31, 2018, the amount of parent company guarantees on lease obligations was $766.3 and $824.5, respectively, the amount of parent company guarantees relating to uncommitted lines of credit was $296.7 and $349.1, respectively, and the amount of parent company guarantees related to daylight overdrafts, primarily utilized to manage intra-day overdrafts due to timing of transactions under cash pooling arrangements without resulting in incremental borrowings, was $205.2 and $207.8, respectively.

Debt and Credit Arrangements Term Loan Agreement (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Term Loan Agreement [Abstract]
Repayments of Debt	$ 100.0

Acquisitions Goodwill and intangible assets (Details) - USD ($) $ in Millions	Jun. 30, 2019	Jun. 30, 2018
Goodwill and intangible assets [Abstract]
Goodwill and intangible assets recorded related to acquisitions	$ 2.4	$ 14.2

Supplementary Data Share Repurchase Program (Details) $ in Millions	Jun. 30, 2019 USD ($)
Disclosure of Repurchase Agreements [Abstract]
Stock repurchase program, remaining authorized repurchase amount, excluding fees	$ 338.4

Acquisitions Number of Acquisitions (Details) - business	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Number of acquisitions [Abstract]
Number of Businesses Acquired	1	2

Income Taxes Change in Unrecognized Tax Benefits (Details) $ in Millions	Jun. 30, 2019 USD ($)
Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 10.0
Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Decrease in unrecognized tax benefits is reasonably possible	$ 20.0

Incentive Compensation Plans Plan Information (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Share-based Payment Arrangement [Abstract]
Performance cash awards granted during the period target value	$ 40.6
Restricted cash awards granted during the period target value	$ 19.6
Cash awards vesting period	3 years

Commitments and Contingencies (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Lease guarantees	$ 766.3	$ 824.5
Credit facility guarantees	296.7	349.1
Cash pooling guarantees	$ 205.2	$ 207.8