Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, attributable to noncontrolling interest, net of taxes	$ (2)	$ (17)	$ (61)	$ (15)
Foreign currency translation adjustments, tax effect	47	(69)	(150)	(21)
Unrealized gains (losses) on securities - tax effect	1	7	28	22
Unrealized gains (losses) on derivatives - tax effect	229	(168)	(574)	(299)
Reclassification adjustment included in net income on derivatives - tax effect	7	2	11	7
Amortization of net prior service credit included in net income, tax effect	$ (150)	$ (112)	$ (451)	$ (332)

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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