Schedule of Future Minimum Rental Payments for Operating Leases (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Minimum Rental Payments
2015	$ 140
2016	120
2017	106
2018	93
2019	76
Thereafter	115
Net minimum lease commitments	650
Minimum Sublease Income
2015	(3)
2016	(2)
2017	(1)
2018	0
2019	(1)
Thereafter	(1)
Net minimum lease commitments	(8)
Operating Leases, Net Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2015	137
2016	118
2017	105
2018	93
2019	75
Thereafter	114
Net minimum lease commitments	$ 642

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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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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