UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating expenses:
Cost of services	$ 417,134	$ 324,782	$ 1,253,765	$ 558,856
Office and general expenses	119,186	121,770	429,121	226,720
Depreciation and amortization	32,207	24,790	95,642	46,122
Impairment and other losses	25,211	14,926	28,034	14,926
Costs and Expenses, Total	593,738	486,268	1,806,562	846,624
Operating Income (Loss), Total	70,053	(19,634)	173,045	10,812
Other income (expense):
Interest expense, net	(19,672)	(11,912)	(56,552)	(15,197)
Foreign exchange, net	(3,927)	(893)	(4,163)	(1,955)
Other, net	147	45,621	182	46,806
Nonoperating Income (Expense), Total	(23,452)	32,816	(60,533)	29,654
Income before income taxes and equity in earnings of non-consolidated affiliates	46,601	13,182	112,512	40,466
Income tax expense	11,540	5,183	20,150	9,205
Income before equity in earnings of non-consolidated affiliates	35,061	7,999	92,362	31,261
Equity in income (loss) of non-consolidated affiliates	213	(76)	1,053	(75)
Net income	35,274	7,923	93,415	31,186
Net income attributable to noncontrolling and redeemable noncontrolling interests	(24,665)	(9,994)	(59,668)	(10,987)
Net income (loss) attributable to Stagwell Inc. common shareholders	$ 10,609	$ (2,071)	$ 33,747	$ 20,199
Earnings Per Share [Abstract]
Earnings per share, basic	$ 0.08	$ (0.06)	$ 0.27	$ (0.06)
Earnings per share, diluted	$ 0.08	$ (0.06)	$ 0.26	$ (0.06)
Weighted Average Number Of Shares Outstanding For Basic and Diluted [Abstract]
Weighted Average Number of Shares Outstanding, Basic	125,384	76,106	124,710	76,106
Weighted Average Number of Shares Outstanding, Diluted	130,498	76,106	131,550	76,106
Revenues	$ 663,791	$ 466,634	$ 1,979,607	$ 857,436