Income Taxes - Reconciliation of the Company's Effective Income Tax Rate to the Federal Statutory Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal income tax at the statutory rate	$ (1,321)	$ 435	$ 5,902
State income taxes, net of federal benefit	935	526	(215)
Difference between statutory and foreign tax rates	(86)	43	7
Permanent differences	794	1,356	1,029
Foreign derived intangible income deduction	(902)	(217)	(304)
Executive compensation limitation	15,463	7,596	1,167
Research and development	(10,246)	(4,911)	(6,908)
Return to provision adjustment	(1,078)	(9)	1,780
Change in liability for unrecognized tax benefits	987	1,191	1,768
Excess stock-based compensation benefit	(9,002)	(4,999)	(8,907)
Change in valuation allowance	163	368	1,984
Tax effects of intercompany transactions	(389)	16	1,004
Other	115	(207)	592
Provision for income taxes (Income tax benefit)	$ (4,567)	$ 1,188	$ (1,101)
Effective tax rate (as a percentage)	72.60%	57.40%	(3.90%)