Consolidated Statements of Total Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement Of Comprehensive Income
Shareholders' comprehensive income (loss)	$ 728	$ 781
Comprehensive income (loss) attributable to noncontrolling interests:
Net income (loss) attributable to redeemable noncontrolling interests	(2)	(1)
Net income (loss) attributable to other noncontrolling interests	(3)	(4)
Other comprehensive income (loss) attributable to redeemable noncontrolling interests	(2)	3
Total comprehensive (loss) attributable to noncontrolling interests	(7)	(2)
Total comprehensive income	$ 721	$ 779

Net of tax amount of other comprehensive income (loss) attributable to redeemable noncontrolling interests.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=51831255

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4613674-111683

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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Portion of net income (loss) attributable to nonredeemable noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Subparagraph (SX 210.5-03.19)
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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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