Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax	$ (198)	$ 126
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), Adjustments, Tax	(3)	117
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	0	0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	$ 1	$ 2

Amount of tax expense (benefit) for adjustments from accumulated other comprehensive income (AOCI) for gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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Amount of tax expense (benefit), after 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.

+ References

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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