Securities - Gains and Losses on Sales of AFS Debt Securities (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
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| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | ||
| Debt securities, available for sale, realized gain | $ 15 | $ 316 |
| Debt securities, available for sale, realized loss | $ 15 | 1 |
| Debt securities, available for sale, net gains | 315 | |
| Debt securities, available for sale, realized gain (loss), income tax expense (benefit) | $ 79 | |
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- Definition Debt Securities, Available-for-sale, Realized Gain (Loss), Income Tax Expense No definition available.
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- References No definition available.
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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