Shareholders' Equity Shareholders' Equity - Common Stock Transactions (Details) (USD $) In Millions, except Per Share data	Apr. 15, 2009	Jul. 26, 2011 July 26 2011 Repurchase of Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Cash paid to repurchase common stock		$ 150
Repurchase of common stock (in shares)		19.7
Repurchase of common stock (in dollars per share)		$ 7.60
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Issuance of common stock (in shares)	69.3
Common stock public offering (in dollars per share)	$ 4.15
Issuance of common stock	276
Stock Issuance, Underwritting Fees and Other Offering Costs	$ 12