Capital and Operating Leases (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Capital and Operaing Lease [Line Items]
Capital Lease Payments in 2013	$ 3
Operating Leases Payments in 2013	26
Capital Lease Payments in 2014	1
Operating Lease Payments in 2014	21
Capital Lease Payments in 2015	0
Operating Lease Payments in 2015	18
Capital Lease Payments in 2016	0
Operating Lease Payments in 2016	16
Capital Lease Payments in 2017	0
Operating Lease Payments in 2017	16
Capital Lease Payments Thereafter	0
Operating Lease Payments Thereafter	66
Capital Lease - Total minimum payments	4
Operating Lease - Total minimum payments	163
Less imputed interest	0
Present value of net minimum lease payments	4
Less current portion	(3)
Non-current portion	$ 1	$ 9

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.