UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenue:
Revenues	$ 706,818	$ 671,168	$ 1,358,558	$ 1,341,227
Operating expenses:
Cost of services	459,216	438,912	871,303	883,438
Office and general expenses	183,061	168,133	362,423	331,476
Depreciation and amortization	41,369	42,001	83,375	76,837
Impairment and other losses	0	215	0	1,715
Costs and Expenses, Total	683,646	649,261	1,317,101	1,293,466
Operating Income (Loss), Total	23,172	21,907	41,457	47,761
Other income (expense):
Interest expense, net	(23,455)	(23,533)	(46,811)	(44,498)
Foreign exchange, net	(1,338)	(1,355)	(118)	(3,613)
Other, net	(360)	193	(111)	(1,074)
Nonoperating Income (Expense), Total	(25,153)	(24,695)	(47,040)	(49,185)
Loss before income taxes and equity in earnings of non-consolidated affiliates	(1,981)	(2,788)	(5,583)	(1,424)
Income tax expense	2,673	1,165	4,395	3,750
Loss before equity in earnings of non-consolidated affiliates	(4,654)	(3,953)	(9,978)	(5,174)
Equity in income (loss) of non-consolidated affiliates	20	(1)	19	507
Net loss	(4,634)	(3,954)	(9,959)	(4,667)
Net (income) loss attributable to noncontrolling and redeemable noncontrolling interests	(627)	989	1,781	420
Net loss attributable to Stagwell Inc. common shareholders	$ (5,261)	$ (2,965)	$ (8,178)	$ (4,247)
Earnings Per Share [Abstract]
Earnings per share, basic	$ (0.02)	$ (0.03)	$ (0.04)	$ (0.04)
Earnings per share, diluted	$ (0.02)	$ (0.03)	$ (0.06)	$ (0.04)
Weighted Average Number Of Shares Outstanding For Basic and Diluted [Abstract]
Weighted Average Number of Shares Outstanding, Basic	260,774	113,484	186,843	113,059
Weighted Average Number of Shares Outstanding, Diluted	260,774	113,484	265,600	113,059