Shareowners' Equity and Noncontrolling Interest (Reclass and Changes in Accumulated Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive (loss) income	$ (7,211)	$ (2,941)	$ (6,661)	$ (2,880)
Other Comprehensive (Loss) Income , before Reclassifications, Net	(708)	(132)
Amounts reclassified, pretax	(244)	101
Tax (benefit) expense reclassified	558us-gaap_IncomeTaxExpenseBenefit	567us-gaap_IncomeTaxExpenseBenefit
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive (loss) income	(300)	(129)	(209)	(79)
Other Comprehensive (Loss) Income , before Reclassifications, Net	(132)	(65)
Amounts reclassified, pretax	(57)	18
Tax (benefit) expense reclassified	16	3
Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax (benefit) expense reclassified	86	30
Accumulated Translation Adjustment [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive (loss) income	(1,718)	71	(1,051)	170
Other Comprehensive (Loss) Income , before Reclassifications, Net	(665)	(102)
Amounts reclassified, pretax	2	3
Tax (benefit) expense reclassified	0	0
Accumulated Defined Benefit Plans Adjustment [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive (loss) income	(5,537)	(3,184)	(5,709)	(3,267)
Other Comprehensive (Loss) Income , before Reclassifications, Net	35	13
Amounts reclassified, pretax	(217)	104
Tax (benefit) expense reclassified	80	34
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive (loss) income	344	301	308	296
Other Comprehensive (Loss) Income , before Reclassifications, Net	54	22
Amounts reclassified, pretax	28	(24)
Tax (benefit) expense reclassified	$ (10)	$ (7)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

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

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

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

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-Name Regulation S-X (SX)

-Number 210

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

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

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

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