Provision for Income Taxes Reconciliations to Recorded Tax Provision (Benefit) Table (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Income Tax Rate Reconciliation [Abstract]
Provision (benefit) at statutory rate		$ 1,255	$ 378	$ 451
Increases (decreases) in taxes resulting from:
Impact of nontaxable noncontrolling interests		(75)	(78)	(72)
State income taxes (net of federal benefit)		82	26	2
Foreign operations - net		(11)	(32)	(36)
Taxes on undistributed earnings of foreign subsidiaries - net	99	(37)	99	0
Other - net		35	8	15
Provision (benefit) for income taxes		$ 1,249us-gaap_IncomeTaxExpenseBenefit	$ 401us-gaap_IncomeTaxExpenseBenefit	$ 360us-gaap_IncomeTaxExpenseBenefit

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).

+ References

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

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-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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