Stock-based Compensation - Stock Option Activity (Details) - Stock Option $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares
Number of Options
Outstanding at beginning of period (shares) | shares		2,847,101
Options granted (shares) | shares	0	5,000
Options exercised (shares) | shares		(665,369)
Options forfeited (shares) | shares		(62,766)
Outstanding at end of period (shares) | shares	2,123,966	2,123,966
Weighted-Average Exercise Price Per Share
Outstanding at beginning of period (USD per share) | $ / shares		$ 13.22
Options granted (USD per share) | $ / shares		29.03
Options exercised (USD per share) | $ / shares		3.98
Options forfeited (USD per share) | $ / shares		25.46
Outstanding at end of period (USD per share) | $ / shares	$ 15.79	$ 15.79
Aggregate Intrinsic Value
Intrinsic value of options exercised | $		$ 21,467
Intrinsic value of options outstanding | $	$ 74,867	$ 74,867