Commitments and Contingencies Noncancelable Operating Leases (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Payments, 2014	$ 363
Future Minimum Payments, 2015	290
Future Minimum Payments, 2016	225
Future Minimum Payments, 2017	156
Future Minimum Payments, 2018	132
Future Minimum Payments, Thereafter	499
Sublease income, 2014	(52)
Sublease income, 2015	(58)
Sublease income, 2016	(60)
Sublease income, 2017	(59)
Sublease income, 2018	(56)
Sublease Income, thereafter	(293)
Net minimum commitment, 2014	311
Net minimum commitment, 2015	232
Net minimum commitment, 2016	165
Net minimum commitment, 2017	97
Net minimum commitment, 2018	76
Net minimum commitment, thereafter	206
Operating Leases, Rent Expense, Net	$ 477	$ 474	$ 556