Securities - Gains and Losses on Sales of AFS Debt Securities (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
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| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | ||||
| Gross gains | $ 1 | $ 102 | $ 3 | $ 156 |
| Gross losses | 0 | 1 | 0 | 3 |
| Net gains on sales of AFS debt securities | 1 | 101 | 3 | 153 |
| Income tax expense attributable to realized net gains on sales of AFS debt securities | $ 1 | $ 38 | $ 1 | $ 58 |
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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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