Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Consolidated Statements of Comprehensive Income [Abstract]
Foreign currency translation adjustments, attributable to noncontrolling interest, net of taxes	$ (51)	$ 0
Foreign currency translation adjustments, tax effect	(62)	49
Unrealized gains (losses) on securities - tax effect	22	5
Unrealized gains (losses) on derivatives - tax effect	(971)	34
Reclassification adjustment included in net income on derivatives - tax effect	0	2
Amortization of net prior service credit included in net income, tax effect	$ (151)	$ (113)

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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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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