Reclassifications from Accumulated Other Comprehensive Income - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity [Abstract]
Transfer of realized losses/(gains) in fair value to earnings	$ 62	$ 59	$ 166	$ 88

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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