Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Consolidated Statements of Comprehensive Income [Abstract]
Foreign currency translation adjustments, attributable to noncontrolling interest, net of taxes	$ 0	$ 2
Foreign currency translation adjustments, tax effect	49	175
Unrealized gains (losses) on securities - tax	5	(4)
Unrealized gains (losses) on derivatives - tax	34	180
Reclassification adjustment included in net income on derivatives - tax effect	2	3
Net prior service credit (cost) arising during period - tax effect	0	185
Amortization of net prior service credit included in net income, tax effect	$ (113)	$ (105)

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.

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