Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Valuation allowance	$ (2,107)	$ (2,624)
Unrecognized tax benefit	14,139	12,683	$ 5,711	$ 3,658
Unrecognized tax benefits that if recognized would reduce income tax expense	10,100
Federal
Income Taxes [Line Items]
Operating loss carryforwards	2,200	2,500
Foreign Tax Authority
Income Taxes [Line Items]
Operating loss carryforwards	7,600	10,600
Unrecognized Tax Benefits Before Interest And Penalties
Income Taxes [Line Items]
Unrecognized tax benefit	$ 12,689	$ 11,505	$ 5,269	$ 3,357