Share-based Compensation - Options (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares
Number of Shares
Options outstanding, beginning balance (in shares) | shares	584,465
Granted (in shares) | shares	0
Exercised (in shares) | shares	(91,299)
Forfeited (in shares) | shares	0
Options outstanding, ending balance (in shares) | shares	493,166
Options vested and exercisable (in shares) | shares	292,744
Weighted Average Exercise Price
Options outstanding, beginning balance (in dollars per share) | $ / shares	$ 23.96
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	24.76
Forfeited (in dollars per share) | $ / shares	0
Options outstanding, ending balance (in dollars per share) | $ / shares	23.81
Options vested and exercisable (in dollars per share) | $ / shares	$ 24.12
Weighted average contractual term	8 years 25 days
Stock Options
Weighted Average Exercise Price
Unrecognized compensation expense | $	$ 1.8
Weighted-average period for recognition of compensation cost	1 year 6 months 7 days