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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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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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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Debt and Capital Lease Obligations (Details) (USD $)	12 Months Ended
Debt and Capital Lease Obligations (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2011
Debt Instruments
Net unamortized discount, including fair value adjustments	$ (21,000,000)		$ (24,000,000)
Total debt	6,354,000,000us-gaap_LongTermDebt		6,525,000,000us-gaap_LongTermDebt
Capital lease obligations, including unamortized fair value adjustments	32,000,000us-gaap_CapitalLeaseObligations		39,000,000us-gaap_CapitalLeaseObligations
Total debt and capital lease obligations	6,386,000,000us-gaap_DebtAndCapitalLeaseObligations		6,564,000,000us-gaap_DebtAndCapitalLeaseObligations
Less current portion	(606,000,000)us-gaap_DebtCurrent		(303,000,000)us-gaap_DebtCurrent
Debt and capital lease obligations, less current portion	5,780,000,000		6,261,000,000
A/R Sales Facility [Member]
Debt Instruments
Long-term debt at stated values	100,000,000	100,000,000	100,000,000	250,000,000
Credit Facilities [Member] \| Bank Credit Facilities [Member]
Debt Instruments
Long-term debt at stated values	0		0
Credit Facilities [Member] \| A/R Sales Facility [Member]
Debt Instruments
Debt instrument, maturity date (year)	Jul. 31, 2015
Long-term debt at stated values	100,000,000		100,000,000
Senior Notes [Member] \| Senior Notes Due In 2015 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2015
Long-term debt at stated values	400,000,000		400,000,000
Interest rate of notes in percentage	4.50%
Senior Notes [Member] \| Senior Notes Due In 2014 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2014
Long-term debt at stated values	0		200,000,000
Interest rate of notes in percentage	4.75%
Senior Notes [Member] \| Senior Notes Due In June 2017 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2017
Long-term debt at stated values	750,000,000		750,000,000
Interest rate of notes in percentage	6.125%
Senior Notes [Member] \| Senior Notes Due In 2020 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2020
Long-term debt at stated values	850,000,000		850,000,000
Interest rate of notes in percentage	6.125%
Senior Notes [Member] \| Senior Notes Due In June 2037 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2037
Long-term debt at stated values	1,500,000,000		1,500,000,000
Interest rate of notes in percentage	6.625%
Senior Notes [Member] \| Senior Notes Due In October 2037 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2037
Long-term debt at stated values	24,000,000		24,000,000
Interest rate of notes in percentage	6.75%
Senior Notes [Member] \| Senior Notes Due In October 2017 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2017
Long-term debt at stated values	200,000,000		200,000,000
Interest rate of notes in percentage	7.20%
Senior Notes [Member] \| Senior Notes Due In 2097 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2097
Long-term debt at stated values	100,000,000		100,000,000
Interest rate of notes in percentage	7.45%
Senior Notes [Member] \| Senior Notes Due In 2032 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2032
Long-term debt at stated values	750,000,000		750,000,000
Interest rate of notes in percentage	7.50%
Senior Notes [Member] \| Senior Notes Due In 2030 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2030
Long-term debt at stated values	200,000,000		200,000,000
Interest rate of notes in percentage	8.75%
Senior Notes [Member] \| Senior Notes Due In 2019 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2019
Long-term debt at stated values	750,000,000		750,000,000
Interest rate of notes in percentage	9.375%
Senior Notes [Member] \| Senior Notes Due In 2039 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2039
Long-term debt at stated values	250,000,000		250,000,000
Interest rate of notes in percentage	10.50%
Debentures [Member] \| Debenture Due In 2026 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2026
Long-term debt at stated values	100,000,000		100,000,000
Interest rate of notes in percentage	7.65%
Debentures [Member] \| Debenture Due In 2015 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2015
Long-term debt at stated values	75,000,000		75,000,000
Interest rate of notes in percentage	8.75%
Debentures [Member] \| Other Debt [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 31, 2015
Long-term debt at stated values	26,000,000		0
Revenue Bonds [Member] \| Gulf Opportunity Zone Revenue Bonds Series 2010 [Member]
Debt Instruments
Debt instrument, maturity date (year)	Dec. 01, 2040	Dec. 01, 2040
Long-term debt at stated values	$ 300,000,000		$ 300,000,000
Interest rate of notes in percentage	4.00%	4.00%