Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Shares
Beginning balance (in shares)	725,864	607,346	725,864	607,346
Options granted (in shares)	250,746
Options exercised (in shares)	(120,000)	(241,214)
Options canceled, forfeited or expired (in shares)	(12,228)
Ending balance (in shares)	725,864	607,346
Options exercisable (in shares)			449,464
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 9.22
Options granted (in dollars per share)	18.11
Options exercised (in dollars per share)	2.58
Options forfeited (in dollars per share)	17.57
Ending balance (in dollars per share)	$ 13.25	$ 9.22
Options exercisable (in dollars per share)			$ 6.33
Weighted Average Remaining Contractual Term (Years)
Options outstanding	3 years 9 months	3 years 5 months 1 day
Options exercisable	1 year 11 months 8 days
Aggregate Intrinsic Value (in millions)
Options outstanding			$ 3.4	$ 5.6
Options exercised	$ 1.8
Options exercisable			$ 3.6