Long-Term Debt (Scheduled Remaining Maturity Of Long-Term Debt) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
2015	$ 17,438,000,000
2016	13,441,000,000
2017	15,544,000,000
2018	5,459,000,000
2019	4,107,000,000
2020 and thereafter	10,117,000,000
Derivative, Amount of Hedged Item	452,000,000us-gaap_DerivativeAmountOfHedgedItem	445,000,000us-gaap_DerivativeAmountOfHedgedItem
Long-term debt	66,558,000,000us-gaap_LongTermDebt	69,465,000,000us-gaap_LongTermDebt
Derivative Instrument Converting Fixed-rate Debt into Variable-rate Obligations	7,400,000,000
Derivative Instrument Converting Variable-rate Debt into Fixed-rate Obligations	2,400,000,000
Unsecured Debt [Member]
Debt Instrument [Line Items]
2015	4,809,000,000
2016	1,865,000,000
2017	4,319,000,000
2018	1,185,000,000
2019	1,593,000,000
2020 and thereafter	8,192,000,000
Derivative, Amount of Hedged Item	452,000,000	445,000,000
Long-term debt	22,415,000,000	27,191,000,000
Secured Debt [Member]
Debt Instrument [Line Items]
Derivative, Amount of Hedged Item	0	0
Long-term debt	44,143,000,000	42,274,000,000
Long-term Debt [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
2015	4,867,000,000
2016	1,934,000,000
2017	4,399,000,000
2018	1,278,000,000
2019	1,625,000,000
2020 and thereafter	9,275,000,000
Derivative, Amount of Hedged Item	452,000,000
Long-term debt	23,830,000,000
Long-term Debt [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
2015	12,629,000,000
2016	11,576,000,000
2017	11,225,000,000
2018	4,274,000,000
2019	2,514,000,000
2020 and thereafter	1,925,000,000
Derivative, Amount of Hedged Item	0
Long-term debt	44,143,000,000
Original Issue Discount [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
2015	(58,000,000)
2016	(69,000,000)
2017	(80,000,000)
2018	(93,000,000)
2019	(32,000,000)
2020 and thereafter	(1,083,000,000)
Derivative, Amount of Hedged Item	0
Long-term debt	$ (1,415,000,000)

Derivative Instrument Converting Fixed-rate Debt into Variable-rate Obligations

No definition available.

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- Definition

Derivative Instrument Converting Variable-rate Debt into Fixed-rate Obligations

+ References

No definition available.

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- Definition

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing 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.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing 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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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth 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.

+ References

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third 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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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second 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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