Noncontrolling and Redeemable Noncontrolling Interests - Noncontrolling Interests (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Noncontrolling Interest [Line Items]
Income attributable to noncontrolling interests	$ 14,884	$ 15,105
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest	15,296	18,231
Noncontrolling interests	508,287	39,787
Stagwell Global
Noncontrolling Interest [Line Items]
Income attributable to noncontrolling interests	6,126	0
Noncontrolling interests	475,373	0
Stagwell Media
Noncontrolling Interest [Line Items]
Income attributable to noncontrolling interests	9,170	18,231
Noncontrolling interests	$ 32,914	$ 39,787

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