Stockholders' Equity (Details Textuals) - USD ($)			1 Months Ended	12 Months Ended
	Jun. 15, 2015	Sep. 14, 2011	Nov. 30, 2008	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Aug. 28, 2015	Jul. 23, 2013	Dec. 06, 2011
Stockholders' Equity Note [Abstract]
Subsidiary equity balance				$ 3,200,000,000
Class of Stock [Line Items]
Common shares, par value (in usd per share)				$ 0.01	$ 0.01
Value authorized but issued					$ 8,500,000
Purchase of preferred stock				$ 1,335,000	$ 2,451,000	$ 1,626,000
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Stock repurchase program authorized amount								$ 10,000,000
Treasury stock shares acquired (in shares)				50,000	88,000
Remaining authorized repurchase amount				$ 5,000,000
Preferred Stock, Dividend Rate, Percentage		8.00%
Depositary shares issued (in shares)		2,600,000
Purchase of preferred stock				1,335,000	$ 2,451,000
Preferred Stock, Dividend Payment Terms		September 15, 2016
Redemption Price On Depositary Shares		$ 1,000
Liquidation preference on depositary shares (in usd per share)		1,000
Depositary share value (in usd per share)		$ 25
Series C Preferred Stock [Member]
Class of Stock [Line Items]
Stock repurchase program authorized amount							$ 10,000,000
Remaining authorized repurchase amount				$ 10,000,000
Preferred Stock, Dividend Rate, Percentage	6.125%
Depositary shares issued (in shares)	2,600,000
Preferred Stock, Dividend Payment Terms	June 15, 2020
Redemption Price On Depositary Shares	$ 1,000
Liquidation preference on depositary shares (in usd per share)	1,000
Depositary share value (in usd per share)	$ 25
Common Stock [Member]
Class of Stock [Line Items]
Treasury stock shares acquired (in shares)				5,000,000	14,300,000
Warrants to purchase shares of common stock (in shares)			$ 4,000,000
Term of warrants			10 years
Exercise price of warrants (in usd per share)			$ 19.77
Common shares, par value (in usd per share)									$ 0.01
Treasury stock carrying basis				$ 93,000,000	$ 259,000,000
Treasury stock acquired average cost per share (in usd per share)				$ 18.73	$ 18.12
Repurchased amount for minimum tax withholding settlement				$ 5,000,000	$ 4,000,000
Repurchased shares for minimum tax withholding settlements (in shares)				285,000	225,000
Minimum tax withholding settlement average cost per share (in usd per share)				$ 17.87	$ 16.50
Remaining authorized repurchase amount				$ 108,000,000