Equity, Changes in Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax
Accumulated other comprehensive income (loss), net of tax	$ 350
Other comprehensive income (loss)	(717)	401	12
Separation of retail business		(479)
Accumulated other comprehensive income (loss), net of tax	(367)	350
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax
Accumulated other comprehensive income (loss), net of tax	350	108	96
Other comprehensive income (loss)	(717)	401	12
Other comprehensive income (loss), before reclassifications, net of tax	(717)	383
Amounts reclassified from accumulated other comprehensive income (loss)	0	18
Separation of retail business		(159)
Accumulated other comprehensive income (loss), net of tax	(367)	350	108
Accumulated Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax
Accumulated other comprehensive income (loss), net of tax	408	665	501
Other comprehensive income (loss)	(407)	(98)	164
Other comprehensive income (loss), before reclassifications, net of tax	(407)	(98)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Separation of retail business		(159)
Accumulated other comprehensive income (loss), net of tax	1	408	665
Accumulated Defined Benefit Plans Adjustment [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax
Accumulated other comprehensive income (loss), net of tax	(58)	(558)	(424)
Other comprehensive income (loss)	(310)	500	(134)
Other comprehensive income (loss), before reclassifications, net of tax	(309)	483
Amounts reclassified from accumulated other comprehensive income (loss)	(1)	17
Separation of retail business		0
Accumulated other comprehensive income (loss), net of tax	(368)	(58)	(558)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax
Accumulated other comprehensive income (loss), net of tax	0	1	19
Other comprehensive income (loss)	0	(1)	(18)
Other comprehensive income (loss), before reclassifications, net of tax	(1)	(2)
Amounts reclassified from accumulated other comprehensive income (loss)	1	1
Separation of retail business		0
Accumulated other comprehensive income (loss), net of tax	$ 0	$ 0	$ 1

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

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