Securities - Gains and Losses on Sales of AFS Debt Securities (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | |||
| Net gains on sales of AFS debt securities | $ 255 | $ 490 | $ 1,138 |
| Debt securities | |||
| Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract] | |||
| Gross gains | 352 | 520 | 1,174 |
| Gross losses | (97) | (30) | (36) |
| Net gains on sales of AFS debt securities | 255 | 490 | 1,138 |
| Income tax expense attributable to realized net gains on sales of AFS debt securities | $ 97 | $ 186 | $ 432 |
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- Definition Available-for-sale Securities, Income Tax Expense on Realized Gain (Loss) Excluding Other Than Temporary Impairments No definition available.
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of loss realized on the sale of debt or equity securities classified as available-for-sale. Excludes other than temporary impairments (OTTI). No definition available.
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- Details
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