Furniture, Equipment and Leasehold Improvements, Net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 29,000	$ 36,200	$ 36,500
Pre-tax real estate charges as part of work force reduction	$ 998	52	28,424
Leasehold improvements, furniture and equipment included in the real estate charges		$ 5,500	$ 4,400