Income Taxes - Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Compensation and benefits	$ 19,353	$ 23,080
Depreciation and amortization	1,539	1,521
Cumulative translation adjustment	12,624	8,878
Operating loss carryforwards	5,256	10,133
Capital loss carryforwards	1,909	2,106
Unrealized loss on investments	90	61
Other financial accruals	5,398	2,047
Valuation allowances	(2,463)	(5,481)
Total deferred tax assets	43,706	42,345
Deferred tax liabilities:
Other financial accruals	3,990	2,928
Total deferred tax liabilities	3,990	2,928
Net deferred tax asset	$ 39,716	$ 39,417