Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 30, 2016
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	1,125.0	1,125.0
Common stock, par value (in dollars per share)	$ 0.20	$ 0.20
Common stock shares outstanding (in shares)	429.0
Common shares unissued but encumbered (in shares)	52.0
Common stock dividends	$ 0	$ 0	$ 0
Net transfers to/from affiliate		$ 0	$ 479,409,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock shares outstanding (in shares)	3.3	3.3
Preferred stock dividend rate (as a percentage)	6.97%
Preferred stock dividend rate (in dollars per share)	$ 3.485
Preferred stock liquidation preference (in dollars per share)	$ 50
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock shares outstanding (in shares)	4.0	4.0
Preferred stock liquidation preference (in dollars per share)	$ 100
Common Stock
Class of Stock [Line Items]
Share price (in dollars per share)				$ 11.02
Three Month LIBOR | Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock dividend rate (as a percentage)	1.70%