Segment Information (Details 3) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Reconciliation from segment income to net income
Total segment income	$ 459	$ 523	$ 923	$ 1,068
Total operating revenues	4,406	1,772	6,102	3,572
Depreciation and amortization	(1,198)	(358)	(1,567)	(711)
Other unassigned operating expenses	(968)	(264)	(1,205)	(522)
Other (expense) income, net	(294)	(136)	(419)	(268)
Income tax expense	(63)	(149)	(191)	(309)
Net income	102	238	313	491
Operating segments
Reconciliation from segment income to net income
Total segment income	2,325	1,039	3,305	2,105
Unallocated amount to segment
Reconciliation from segment income to net income
Total operating revenues	253	139	388	277
Other unassigned operating expenses	$ (921)	$ (297)	$ (1,203)	$ (603)