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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Oct. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Impairment					$ 16,224
Intangible amortization	$ 1,953		$ 2,353		6,170	$ 6,869
On-Demand Talent Reporting Unit
Finite-Lived Intangible Assets [Line Items]
Goodwill forecast margin, percentage							6.00%
Impairment		$ 14,800			14,800
Europe Reporting Unit
Finite-Lived Intangible Assets [Line Items]
Impairment		$ 1,500			$ 1,500
Heidrick Consulting Reporting Unit
Finite-Lived Intangible Assets [Line Items]
Impairment				$ 7,200		$ 7,200
BusinessFourZero
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired				$ 7,100