Disposals and Discontinued Operations Disposals and Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Income	$ 267	$ 406	$ 294	$ 312	$ 346	$ 398	$ 288	$ 389	$ 1,279	$ 1,421	$ 1,470
Income Tax Benefit							87		286	268	315
Net Loss	(56.00)	1.00	(1.00)	0	(1.00)	0	(1.00)	(1.00)	(56.00)	(3.00)	(8.00)
Segment, Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue									55	39	32
Disposal Group, Including Discontinued Operation, Operating Expense									24	16	11
Depreciation and Amortization, Discontinued Operations									23	18	15
Taxes Other than Income Related to Discontinued Operations									4	3	2
Assets (Gains) and Losses Related to Sale of Segment									83	0	10
Expenses from Discontinued Operations									134	37	38
Operating Income									(79)	2	(6)
Other (income) and deductions									6	6	6
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax									(85)	(4)	(12)
Income Tax Benefit									(29)	(1)	(4)
Net Loss									$ (56.00)	$ (3.00)	$ (8.00)