Income Taxes - Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 4,665	$ 3,165
Additions based on tax positions related to current year	1,102	753
Additions based on tax positions related to prior years	1,317	747
Balance at end of year	$ 7,084	$ 4,665