Income Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Valuation Allowances and Reserves, Period Increase (Decrease)	$ (14,000,000)	$ (58,000,000)
Income tax loss carryforwards	1,100,000,000
Income tax loss carryforwards expire amount	491,000,000
Income tax loss carryforwards expiration dates	2013 through 2032
Remaining amount of loss carryforwards that has no expiration date	638,000,000
Unremitted earnings	9,500,000,000
Unrecognized tax benefits	276,000,000
Income Tax Penalties And Interest Accrued	not significant	not significant	not significant
Total accrued penalties and net accrued interest	47,000,000	25,000,000
Aggregate resolution of uncertainties	200,000,000
Year federal income tax returns have been audited	2009
Administrative appeals or litigation	1999 to 2009
Pending refund actions, period	two
State and Local Jurisdiction [Member]
Statute for potential adjustments, period	3 to 5 years
Impact on Earnngs [Member]
Valuation Allowances and Reserves, Period Increase (Decrease)	$ 3,000,000	$ 36,000,000