Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jun. 30, 2010 Foreign Tax Authority [Member]	Dec. 31, 2012 Foreign Tax Authority [Member]	Dec. 31, 2010 Foreign Tax Authority [Member]	Jun. 02, 2012 Foreign Tax Authority [Member]
Future Minimum Rental Payments
Operating leases minimum payments due in 2013	$ 337
Operating leases minimum payments due in 2014	250
Operating leases minimum payments due in 2015	179
Operating leases minimum payments due in 2016	133
Operating leases minimum payments due in 2017	86
Operating leases minimum payments due - Thereafter	350
Total minimum rental payments under operating leases	1,335
Minimum rentals to be received under subleases	30
Rental Expense
Minimum rental expense	508	523	485
Contingent rental expense	23	23	23
Total rental expense	531	546	508
Less sublease rental income	(2)	(2)	(3)
Net rental expense	529	544	505
Commitments and Contingencies (Textual)
Minimum range of possible loss contingency	0
Maximum range of possible loss contingency	250
Profit tax rate under new tax regime					7.00%
Dividend tax rate under new tax regime					0.00%
Projected minimum annual prepayment of taxes							10
Payment made under the settlement				118
Gain on settlement of tax with GOA						30
Reduction to interest expense due to settlement						(8)
Income tax benefit on settlement						$ (20)