Earnings per Share - Schedule of Reconciliation of the Numerators and Denominators of the Basic and Diluted Net Income Per Share Computations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income available to common stockholders	$ 38,229	$ 20,855
Shares outstanding:
Weighted average shares outstanding – basic	77,567,147	77,353,730
Weighted average shares outstanding – diluted	78,589,110	78,080,049
Net income per common share attributable to common stockholders – basic:	$ 0.49	$ 0.27
Net income per common share attributable to common stockholders – diluted:	$ 0.49	$ 0.27
Stock Options
Shares outstanding:
Effect of dilutive securities	104,382	152,906
Restricted Stock Units (RSUs)
Shares outstanding:
Effect of dilutive securities	917,581	573,413