Securities - Gains and Losses on Sales of AFS Debt Securities (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
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| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | ||||
| Gross gains | $ 83 | $ 130 | $ 86 | $ 286 |
| Gross losses | (10) | (5) | (10) | (8) |
| Net gains on sales of AFS debt securities | 73 | 125 | 76 | 278 |
| Income tax expense attributable to realized net gains on sales of AFS debt securities | $ 17 | $ 48 | $ 18 | $ 106 |
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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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- 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). No definition available.
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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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- References No definition available.
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