Earnings per Share - Basic (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Basic earnings per share:
Net income (loss) available for common stockholders	$ 289,441	$ 2,939	$ 32,980
Less: Dividends and undistributed earnings allocated to participating securities	(5,418)	(1,326)	(809)
Net income (loss) available for common stockholders, net of dividends and undistributed earnings allocated to participating securities	$ 284,023	$ 1,613	$ 32,171
Weighted average shares of common stock outstanding:
Outstanding (in shares)	100,875,793	62,579,147	38,539,091
Basic earnings per share (in dollars per share)	$ 2.82	$ 0.03	$ 0.83
Class A
Weighted average shares of common stock outstanding:
Outstanding (in shares)	100,875,793	62,579,147	38,539,091