Stockholders Equity (Details Textuals) (USD $)	0 Months Ended	12 Months Ended
	Jan. 15, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Nov. 30, 2008 Common Stock
Stockholders' Equity Note [Abstract]
Stock issued during period new issue, shares	44,800,000
Stock Issued During Period Price Per Share New Issues	$ 11.15
Stock issued during period new issue, value				$ 478,358,000
Depositary Shares Issued			2,600,000
Rate On Depositary Shares Issued			8.00%
Liquidation Preference On Depositary Shares			$ 1,000
Depositary Share Per Share Value			$ 25
Depositary Shares Issued As Interest In Eight Percent Perpetual Preferred Stock			On September 14, 2011, the Corporation issued 2,600,000 depositary shares, each representing a 1/40th interest in a share of the Corporation’s 8.00% Perpetual Preferred Stock, Series B, liquidation preference $1,000 per share (the “Series B Preferred Stock”).
Subsidiary Equity Balance		3,200,000,000
Amount Available for Dividend Distribution without Prior Approval from Regulatory Agency		231,000,000
StockRepurchaseProgramAuthorizedAmount		125,000,000
TreasuryStockSharesAcquired		4,700,000
TreasuryStockCarryingBasis		$ 60,000,000
TreasuryStockAcquiredAverageCostPerShare		$ 12.77
Class Of Warrant Or Right [Abstract]
Period warrants are exercisable					exercisable at any time, in whole or in part
Exercise price of warrants					$ 19.77