Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statements of Comprehensive Income [Abstract]
Foreign currency translation adjustments, attributable to noncontrolling interest, net of taxes	$ (10)	$ 0	$ (4)	$ 0
Foreign currency translation adjustments, tax effect	115	136	506	126
Unrealized gains (losses) on available-for-sale securities - tax	29	2	44	(13)
Reclassification adjustment included in net income on available-for-sale securities - tax effect	(7)	2	(4)	0
Unrealized gains (losses) on cash flow hedges - tax	(279)	(208)	(272)	(141)
Reclassification adjustment included in net income on cash flow hedges - tax effect	5	5	10	10
Net prior service credit (cost) arising during period - tax effect	594	0	594	0
Amortization of net prior service credit included in net income, tax effect	$ (151)	$ (131)	$ (290)	$ (262)

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to noncontrolling interests.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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