Employee Benefit Plans - Stock Activity, Weighted Average Exercise Price (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Shares
Options outstanding, beginning balance (in shares)	10,284,498
Granted (in shares)	581,000	85,000
Exercised (in shares)	(1,811,274)
Forfeited (in shares)	(33,333)
Options outstanding, end balance (in shares)	9,020,891		10,284,498
Options exercisable (in shares)	2,284,519
Options unvested (in shares)	6,736,372
Weighted Average Exercise Price
Options outstanding, beginning balance, weighted-average exercise price	$ 5.78
Granted, weighted-average exercise price	65.72
Exercised, weighted-average exercise price	2.65
Forfeited, weighted-average exercise price	1.74
Options outstanding, end balance, weighted-average exercise price	15.18		$ 5.78
Options exercisable, weighted-average exercise price	2.07
Options unvested, weighted-average exercise price	$ 11.73
Stock option activity additional disclosures
Options outstanding, weighted-average remaining contractual term	8 years 1 month 6 days		7 years 9 months 18 days
Options exercisable, weighted-average remaining contractual term	5 years 8 months 12 days
Options unvested, weighted-average remaining contractual term	8 years 10 months 24 days
Options outstanding, aggregate intrinsic value	$ 247,964		$ 289,316
Options exercisable, aggregate intrinsic value	77,143
Options unvested, aggregate intrinsic value	$ 170,820
Weighted-average grant date fair value of options granted (per share)	$ 31.78	$ 2.80
Unrecognized compensation cost	$ 40,500
Period for recognition	3 years
Fair value of stock options that vested during the period	$ 2,900	$ 1,200