Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income attributable to common stockholders - basic									$ 70,114	$ 62,975	$ 25,773
Interest expense attributable to convertible notes									0	10,742	0
Net income attributable to common stockholders - diluted									$ 70,114	$ 73,717	$ 25,773
Weighted average common shares outstanding (in shares)									52,615,977	43,123,222	43,084,671
Weighted average restricted stock shares (in shares)									471,418	322,162	150,000
Weighted average basic common shares outstanding (in shares)	54,853,205	54,853,205	53,953,634	48,601,431	43,502,583	43,456,234	43,446,963	43,374,228	53,087,395	43,445,384	43,234,671
Effect of dilutive shares issued in an assumed conversion of the convertible senior notes (in shares)									0	8,594,613	0
Weighted average diluted common shares outstanding (in shares)	54,853,205	54,853,205	67,624,395	62,256,595	56,264,771	50,651,612	50,634,463	50,467,978	53,087,395	52,039,997	43,234,671
Basic earnings per weighted average common share (in usd per share)	$ 0.32	$ 0.32	$ 0.34	$ 0.35	$ 0.38	$ 0.38	$ 0.35	$ 0.34	$ 1.32	$ 1.45	$ 0.60
Diluted earnings per weighted average common share (in usd per share)	$ 0.32	$ 0.32	$ 0.33	$ 0.34	$ 0.37	$ 0.37	$ 0.34	$ 0.33	$ 1.32	$ 1.42	$ 0.60
Interest expense attributable to antidilutive convertible notes excluded from computation of earnings per share									$ 18,000		$ 400
Antidilutive convertible notes excluded from computation of earnings per share (in shares)									13,670,796		668,449