Equity (Details Textuals) (USD $) In Millions, except Share data	3 Months Ended		9 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Mar. 31, 2011 Convertible Preferred Stock	Dec. 31, 2010 Convertible Preferred Stock	Sep. 30, 2011 Convertible Preferred Stock
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock, shares issued						6,857,000	0
Preferred stock, par value						$ 0.01	$ 0.01
Preferred stock, aggregate liquidation preference						$ 0.01
Fair Value of Stock Issued						$ 2,805
Redemption premium on convertible preferred stock	0	0	146	0	146
Convertible Preferred Stock Redemption Date					Mar. 08, 2011
Redemption of Convertible Preferred Stock					$ 2,951