Income Taxes - Reconciliation of Total Amounts of Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	$ 8,418	$ 2,886	$ 731
Gross increases—tax positions in prior years	0	3,259	1,503
Gross decreases—tax positions in prior years	(760)	(8)	(257)
Gross increases—tax positions in current year	1,703	2,284	956
Settlements	(4)	0	(40)
Lapse of statute of limitations	(3)	(3)	(7)
Balance at end of period	$ 9,354	$ 8,418	$ 2,886