Net Income Per Share - Reconciliation of Basic and Diluted Net Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net Income
Net income available to common stockholders	$ 34,263	$ 38,817
Diluted net income per share	$ 34,263	$ 38,817
Weighted-Average Shares
Net income available to common stockholders (in shares)	54,732,073	49,369,024
Effect of potentially dilutive stock options and restricted stock awards (in shares)	185,687	171,820
Diluted net income per share (in shares)	54,917,760	49,540,844
Per Share Amount
Net income available to common stockholders (in dollars per share)	$ 0.63	$ 0.79
Diluted net income per share (in dollars per share)	$ 0.62	$ 0.78