Securities - Rollforward of Credit Losses Recognized (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2017 |
Jun. 30, 2016 |
Jun. 30, 2017 |
Jun. 30, 2016 |
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| Rollforward of OTTI Credit Losses Recognized | ||||
| Balance, beginning of period | $ 279 | $ 269 | $ 253 | $ 266 |
| Additions for credit losses recognized on AFS debt securities that had no previous impairment losses | 5 | 1 | 9 | 2 |
| Additions for credit losses recognized on AFS debt securities that had previously incurred impairment losses | 1 | 4 | 23 | 10 |
| Reductions for AFS debt securities matured, sold or intended to be sold | (1) | (28) | (1) | (32) |
| Balance, June 30 | $ 284 | $ 246 | $ 284 | $ 246 |
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- Definition Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions No definition available.
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- Definition This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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