Income Taxes - Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Compensation and benefits	$ 32,021	$ 30,680
Depreciation and amortization	2,483	2,637
Cumulative translation adjustment	20,361	17,503
Operating loss carryforwards	4,944	3,906
Capital loss carryforwards	1,938	2,426
Foreign tax credit carryforwards	0	312
Other financial accruals	2,299	1,346
Valuation allowances	(1,938)	(2,738)
Total deferred tax assets	62,108	56,072
Deferred tax liabilities:
Unrealized gain on investments	659	242
Other financial accruals	3,008	1,338
Total deferred tax liabilities	3,667	1,580
Net deferred tax asset	$ 58,441	$ 54,492