Securities - Gains and Losses on Sales of AFS Debt Securities (Details) - USD ($) $ in Millions |
3 Months Ended | |
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Mar. 31, 2019 |
Mar. 31, 2018 |
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| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | ||
| Gross gains | $ 117 | $ 2 |
| Gross losses | (111) | 0 |
| Net gains on sales of AFS debt securities | 6 | 2 |
| Income tax expense attributable to realized net gains on sales of AFS debt securities | $ 2 | $ 0 |
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- Definition Debt Securities, Available-for-sale, Income Tax Expense on Realized Gain (Loss), Excluding Other Than Temporary Impairments 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), excluding other-than-temporary impairment (OTTI). No definition available.
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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), excluding other-than-temporary impairment (OTTI). No definition available.
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