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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Oct. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Impairment			$ 16,224
Intangible amortization	$ 1,920	$ 2,647	4,217	$ 4,516
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