Furniture, Equipment and Leasehold Improvements, Net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 34,200	$ 32,800	$ 29,400
Real estate charges	$ 7,160	$ 36,669	$ 17,704

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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