Bryanston Settlement (Details) - USD ($) $ in Thousands			12 Months Ended
	Mar. 07, 2016	Feb. 12, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Dividends payable upon settlement event			$ 263	$ 0	$ 0
Interest expense			419	2,616	9,128
Series E
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Payments for Repurchase of Private Placement	$ 30,700
Redemption of preferred stock	$ 1,500
Mandatorily Redeemable Preferred Stock
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Dividends payable upon settlement event		$ 1,200
Mandatorily Redeemable Preferred Stock | Series E
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest expense			$ 231	$ 1,200	$ 7,700