Long-Term Debt (Details 1) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Long-Term Debt (Table Amounts) [Abstract]
Long-term debt	$ 6,526
Capital leases	31	$ 33
Other long-term debt	245	245
Debt and Capital Lease Obligations	6,526	5,928
Less: current portion	110	3
Long-term debt, net of current portion	$ 6,416	5,925
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
2045
Long-Term Debt (Table Amounts) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	3.85%
Long-term debt	$ 600
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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Paragraph 16
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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