Long-Term Debt (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Long-Term Debt (Table Amounts) [Abstract]
Long-term debt	$ 5,928us-gaap_LongTermDebt
Capital leases	33us-gaap_CapitalLeaseObligations	35us-gaap_CapitalLeaseObligations
Other long-term debt	245us-gaap_OtherLongTermDebt	245us-gaap_OtherLongTermDebt
Debt and Capital Lease Obligations	5,928us-gaap_DebtAndCapitalLeaseObligations	5,930us-gaap_DebtAndCapitalLeaseObligations
Less: current portion	3	2
Long-term debt, net of current portion	5,925	5,928
2016
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	7.75%
Long-term debt	107	107
2018
Long-Term Debt (Table Amounts) [Abstract]
Long-term debt	1,050	1,050
2019
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	5.05%
Long-term debt	500	500
2021
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Long-term debt	700	700
2023
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Long-term debt	1,050	1,050
2026
Long-Term Debt (Table Amounts) [Abstract]
Long-term debt	527	527
2031
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	7.75%
Long-term debt	466	466
2040
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	5.05%
Long-term debt	300	300
2043
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	4.75%
Long-term debt	$ 950	$ 950
Minimum \| 2018
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	1.75%
Minimum \| 2026
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	7.75%
Maximum \| 2018
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Maximum \| 2026
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	7.88%

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.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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