Employee Benefit Plans - Stock Transactions - Stock Options Outstanding And Exercisable (Details)	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Options outstanding (in shares) | shares	749,333
Options outstanding, Weighted average remaining contractual life (in years)	7 years 1 month 6 days
Options outstanding, Weighted average exercise price (in dollars per share)	$ 16.91
Options exercisable (in shares) | shares	367,869
Options exercisable, Weighted average exercise price (in dollars per share)	$ 15.18
$0.00 - $6.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Range of exercise prices, lower	0.00
Range of exercise prices, upper	$ 6.00
Options outstanding (in shares) | shares	33,000
Options outstanding, Weighted average remaining contractual life (in years)	1 year 4 months 24 days
Options outstanding, Weighted average exercise price (in dollars per share)	$ 5.59
Options exercisable (in shares) | shares	33,000
Options exercisable, Weighted average exercise price (in dollars per share)	$ 5.59
$6.01 - $12.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Range of exercise prices, lower	6.01
Range of exercise prices, upper	$ 12.00
Options outstanding (in shares) | shares	146,800
Options outstanding, Weighted average remaining contractual life (in years)	4 years 2 months 12 days
Options outstanding, Weighted average exercise price (in dollars per share)	$ 8.95
Options exercisable (in shares) | shares	146,800
Options exercisable, Weighted average exercise price (in dollars per share)	$ 8.95
$12.01 - $18.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Range of exercise prices, lower	12.01
Range of exercise prices, upper	$ 18.00
Options outstanding (in shares) | shares	132,533
Options outstanding, Weighted average remaining contractual life (in years)	7 years 9 months 18 days
Options outstanding, Weighted average exercise price (in dollars per share)	$ 16.37
Options exercisable (in shares) | shares	69,201
Options exercisable, Weighted average exercise price (in dollars per share)	$ 15.72
$18.01 - $24.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range
Range of exercise prices, lower	18.01
Range of exercise prices, upper	$ 24.00
Options outstanding (in shares) | shares	437,000
Options outstanding, Weighted average remaining contractual life (in years)	8 years 3 months 18 days
Options outstanding, Weighted average exercise price (in dollars per share)	$ 20.61
Options exercisable (in shares) | shares	222,178
Options exercisable, Weighted average exercise price (in dollars per share)	$ 20.56