CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net income	$ 65,842	$ 35,920	$ 71,461
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Stock-based compensation	33,152	75,032
Depreciation and amortization	131,273	77,503	41,025
Impairment and other losses	122,179	16,240	0
Provision for bad debt expense	7,755	2,031	6,222
Deferred income taxes	(18,319)	(3,818)	(5,463)
Adjustment to deferred acquisition consideration	(13,405)	18,721	4,520
Gain on sale of asset	0	(43,440)
Interest from preferred investments	0	0	(600)
Transaction costs contributed by Stagwell Media LP	0	0	10,160
Foreign currency translation loss on foreign denominated debt	0	0	721
Other, net	(5,692)	(1,463)	1,271
Changes in working capital:
Accounts receivable	37,780	(30,784)	(26,805)
Expenditures billable to clients	(32,366)	(35,371)	10,078
Other assets	1,179	3,997	(10,461)
Accounts payable	98,871	(46,356)	5,606
Accrued expenses and other liabilities	(42,808)	61,974	22,922
Advance billings	(27,062)	76,021	7,423
Deferred acquisition related payments	(10,793)	(5,351)
Net Cash Provided by (Used in) Operating Activities, Total	347,586	200,856	138,080
Cash flows from investing activities:
Capital expenditures	(22,663)	(8,797)	(4,690)
Current period acquisitions, net of cash acquired	(74,234)	150,346	(14,732)
Proceeds from sale of business, net	0	37,232
Capitalized software and other	(19,378)	(14,829)	(9,599)
Net Cash Provided by (Used in) Investing Activities, Total	(116,275)	163,952	(29,021)
Repayment of borrowings under revolving credit facility
Repayment of borrowings under revolving credit facility	(1,266,000)	(719,088)	(126,994)
Proceeds from borrowings under revolving credit facility	1,255,500	516,669	167,000
Shares acquired and cancelled	18,729	841	0
Distributions to noncontrolling interests and other	(39,197)	0	0
Payment of deferred consideration	(63,170)	0	(1,000)
Contributions	0	0	1,554
Purchase of noncontrolling interest	3,600	37,500	1,559
Proceeds from issuance of the 5.625% Notes	0	1,100,000	0
Debt issuance costs	0	(15,053)	(3,099)
Payment of deferred consideration	0	0	500
Distributions	0	(233,203)	(115,543)
Repurchase of 7.50% Senior Notes	0	(884,398)	0
Repurchase of Common Stock	(51,540)	0	0
Net Cash Provided by (Used in) Financing Activities, Total	(186,736)	(273,414)	(80,141)
Effect of exchange rate changes on cash and cash equivalents	(7,995)	158	(321)
Net increase in cash and cash equivalents	36,580	91,552	28,597
Cash and cash equivalents at beginning of period	184,009	92,457	63,860
Cash and cash equivalents at end of period	220,589	184,009	92,457
Supplemental Cash Flow Information:
Cash income taxes paid	46,275	58,578	10,714
Cash interest paid	70,935	23,528	9,287
Non-cash investing and financing activities:
Acquisitions of business	1,178	425,752	23,720
Acquisitions of noncontrolling interest	1,000	170,266
Issuance of Redeemable Noncontrolling Interest		27,820
Net unrealized gain on available for sale investment	0	0	5,156
Establishment of a deferred tax asset related to the exchange	32,890	0
Establishment of Tax Receivables Agreement liability	28,694	0
Non-cash contributions	0	12,372	93,880
Non-cash distributions to Stagwell Media LP	0	13,000
Non-cash payment of deferred acquisition consideration	$ 989	7,080	$ 64,345
Conversion of preferred shares		$ 209,947