Goodwill and Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Goodwill [Roll Forward]
Goodwill beginning of period	$ 1,242,777
Foreign currency translation adjustment	(2,942)
Goodwill end of period	1,239,835
Corporate Finance
Goodwill [Roll Forward]
Goodwill beginning of period	543,243
Foreign currency translation adjustment	(848)
Goodwill end of period	542,395
Accumulated impairment loss	0	$ 0
FLC
Goodwill [Roll Forward]
Goodwill beginning of period	215,174
Foreign currency translation adjustment	(630)
Goodwill end of period	214,544
Accumulated impairment loss	0	0
Economic Consulting
Goodwill [Roll Forward]
Goodwill beginning of period	268,920
Foreign currency translation adjustment	(159)
Goodwill end of period	268,761
Accumulated impairment loss	0	0
Technology
Goodwill [Roll Forward]
Goodwill beginning of period	96,887
Foreign currency translation adjustment	(30)
Goodwill end of period	96,857
Accumulated impairment loss	0	0
Strategic Communications
Goodwill [Roll Forward]
Goodwill beginning of period	118,553
Foreign currency translation adjustment	(1,275)
Goodwill end of period	117,278
Accumulated impairment loss	194,100	194,100
Goodwill	$ 311,400	$ 312,700

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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