Equity - Preferred Stock (Details) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Preferred stock, shares outstanding (in shares)	3,600,000	3,600,000
Preferred Stock, Dividend Rate, Percentage	5.875%	5.875%
Preferred stock, liquidation preference (in dollars per share)	$ 25	$ 25
Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage	5.875%