Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Consolidated Statements of Comprehensive Income [Abstract]
Foreign currency translation adjustments, attributable to noncontrolling interest, net of taxes	$ (17)	$ (7)	$ (15)	$ (37)
Foreign currency translation adjustments, tax effect	(69)	(2)	(21)	(145)
Unrealized gains (losses) on securities - tax effect	7	(4)	22	(8)
Unrealized gains (losses) on derivatives - tax effect	(168)	0	(299)	68
Reclassification adjustment included in net income on derivatives - tax effect	2	3	7	9
Net prior service credit (cost) arising during period - tax effect	0	0	0	173
Amortization of net prior service credit included in net income, tax effect	$ (112)	$ (108)	$ (332)	$ (322)

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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