Equity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			$ 7,651	$ 7,514
Net income	275	333	341	532
Total foreign currency translation adjustment, net of income tax	(29)	(182)	(18)	(217)
Total change in derivative fair value, net of income tax	(92)	163	(193)	171
Total pension adjustments, net of income tax	25	13	31	27
Capital contributions from noncontrolling interests			113	55
Distributions to noncontrolling interests			(215)	(226)
Disposition of businesses			(151)	(21)
Acquisition of treasury stock			(32.0)	(18.0)
Issuance and exercise of stock-based compensation benefit plans, net of income tax			16	24
Dividends declared on common stock ($0.05 per share)			(36)	(60)
Sale of subsidiary shares to noncontrolling interests			0	33
Transaction between entities under common control			7	0
Acquisition of subsidiary shares from noncontrolling interests			(6)	(7)
Ending Balance	7,508	7,807	7,508	7,807
Unrealized Derivative Losses [Roll Forward]
Unrealized derivative losses, beginning balance			(307)
Other comprehensive income before reclassifications			(116)
Amount reclassified from accumulated other comprehensive loss			17
Net current-period other comprehensive income			(99)
Unrealized derivative losses, ending balance	(406)		(406)
Unfunded PensionObligation [Roll Forward]
Unfunded pension obligation, beginning balance			(291)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax			9
Amount reclassified from accumulated other comprehensive loss			5
Net current-period other comprehensive income			14
Unfunded pension obligation, ending balance	(277)		(277)
Foreign Currency Translation Adjustment [Roll Forward]
Foreign currency translation adjustment, beginning balance			(2,284)
Other comprehensive income before reclassification			(9)
Amounts reclassified from accumulated other comprehensive income			(47)
Net current-period other comprehensive income			(56)
Foreign currency translation adjustment, ending balance	(2,340)		(2,340)
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Accumulated other comprehensive loss, beginning balance			(2,882)
Other comprehensive income before reclassifications			(116)
Amounts reclassified from accumulated other comprehensive loss			(25)
Net current-period other comprehensive income			(141)
Accumulated other comprehensive loss, ending balance	(3,023)		(3,023)
Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			4,330	4,569
Net income			75	249
Total foreign currency translation adjustment, net of income tax			(56)	(148)
Total change in derivative fair value, net of income tax			(99)	123
Total pension adjustments, net of income tax			14	6
Capital contributions from noncontrolling interests			0	0
Distributions to noncontrolling interests			0	0
Disposition of businesses			0	(1)
Acquisition of treasury stock			(32.0)	(18.0)
Issuance and exercise of stock-based compensation benefit plans, net of income tax			16	24
Dividends declared on common stock ($0.05 per share)			(36)	(60)
Sale of subsidiary shares to noncontrolling interests			0	11
Transaction between entities under common control			5	0
Acquisition of subsidiary shares from noncontrolling interests			(6)	(6)
Ending Balance	4,211	4,749	4,211	4,749
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			3,321	2,945
Net income			266	283
Total foreign currency translation adjustment, net of income tax			38	(69)
Total change in derivative fair value, net of income tax			(94)	48
Total pension adjustments, net of income tax			17	21
Capital contributions from noncontrolling interests			113	55
Distributions to noncontrolling interests			(215)	(226)
Disposition of businesses			(151)	(20)
Acquisition of treasury stock			0	0
Issuance and exercise of stock-based compensation benefit plans, net of income tax			0	0
Dividends declared on common stock ($0.05 per share)			0	0
Sale of subsidiary shares to noncontrolling interests			0	22
Transaction between entities under common control			2	0
Acquisition of subsidiary shares from noncontrolling interests			0	(1)
Ending Balance	$ 3,297	$ 3,058	$ 3,297	$ 3,058