Net Income Per Share - Reconciliation of Basic and Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net Income
Net income available to common stockholders	$ 52,770	$ 36,210	$ 157,798	$ 103,465
Diluted net income per share	$ 52,770	$ 36,210	$ 157,798	$ 103,465
Weighted-Average Shares
Net income available to common stockholders (in shares)	53,766,630	53,843,508	53,883,945	54,111,848
Effect of potentially dilutive stock options and restricted stock awards (in shares)	193,135	127,090	209,118	166,034
Diluted net income per share (in shares)	53,959,765	53,970,598	54,093,063	54,277,882
Per Share Amount
Net income available to common stockholders (in dollars per share)	$ 0.98	$ 0.67	$ 2.93	$ 1.91
Diluted net income per share (in dollars per share)	$ 0.98	$ 0.67	$ 2.92	$ 1.91