Derivative And Hedging Activities (Interest Income And Interest Expense Disclosure) (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Derivative And Hedging Activities [Abstract]
Interest expense on senior notes	$ 152	$ 167	$ 494	$ 550
Interest expense on credit facilities	18	18	49	42
Gains (losses) on interest rate derivatives			19	(81)
Amortization of loan discount and other	8	3	30	26
Capitalized interest	(174)	(185)	(555)	(525)
Total interest expense	$ 4	$ 3	$ 37	$ 12