Noncontrolling and Redeemable Noncontrolling Interests - Changes in Noncontrolling Interests (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Noncontrolling Interest [Line Items]
Net income (loss) attributable to Stagwell Inc.:	$ 21,036	$ 56,356
Change from net income (loss) attributable to Stagwell Inc. and transfers to noncontrolling interests	(5,502)	56,356
Stagwell Inc. Shareholders' Equity
Noncontrolling Interest [Line Items]
Purchase of noncontrolling interests	$ (26,538)	$ 0

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

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+ Details