Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill	$ 1,396,906
Accumulated goodwill impairment	(194,139)
Goodwill	1,202,767
Foreign currency translation adjustment and other	(10,819)
Goodwill	1,386,087
Accumulated goodwill impairment	(194,139)
Goodwill	1,191,948
Corporate Finance & Restructuring
Goodwill [Roll Forward]
Goodwill	478,842
Goodwill	478,842
Foreign currency translation adjustment and other	(3,771)
Goodwill	475,071
Goodwill	475,071
Forensic and Litigation Consulting
Goodwill [Roll Forward]
Goodwill	232,120
Goodwill	232,120
Foreign currency translation adjustment and other	(1,802)
Goodwill	230,318
Goodwill	230,318
Economic Consulting
Goodwill [Roll Forward]
Goodwill	268,677
Goodwill	268,677
Foreign currency translation adjustment and other	(331)
Goodwill	268,346
Goodwill	268,346
Technology
Goodwill [Roll Forward]
Goodwill	96,770
Goodwill	96,770
Foreign currency translation adjustment and other	(81)
Goodwill	96,689
Goodwill	96,689
Strategic Communications
Goodwill [Roll Forward]
Goodwill	320,497
Accumulated goodwill impairment	(194,139)
Goodwill	126,358
Foreign currency translation adjustment and other	(4,834)
Goodwill	315,663
Accumulated goodwill impairment	(194,139)
Goodwill	$ 121,524

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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