Commitments and Contingencies (Details 3) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Future minimum payments under operating leases:
2013	$ 177
2014	149
2015	124
2016	102
2017	94
2018 and thereafter	575
Total future minimum payments	1,221
Minimum sublease rentals due in the future under non-cancelable subleases	106
Purchase Obligations
Total purchase commitments	341
2013	66
2014 through 2015	99
2016 through 2017	82
2018 and thereafter	$ 94

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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