Securities - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Debt Securities, Available-for-sale [Line Items] | ||
| Fair Value | $ 229,366 | $ 302,631 |
| Unrealized mark-to-market net gains (losses) | (73) | 243 |
| Realized net gains (losses) | 140 | (49) |
| Other assets | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Equity securities, fair value | 893 | |
| Equity securities, cost | 219 | |
| Time Deposits Placed and Other Short-term Investments | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Time deposits placed and other short-term investments | 1,200 | |
| Nonperforming Financing Receivable | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Fair Value | 11 | $ 99 |
| Debt securities | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Accumulated net unrealized loss on AFS debt securities | 3,700 | |
| Accumulated other comprehensive income tax expense (benefit) | $ (1,200) | |
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- Definition Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Tax No definition available.
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- Definition Other Debt Securities Carried at Fair Value, Realized Gains (Losses) No definition available.
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- Definition Other Debt Securities Carried at Fair Value, Unrealized Gains (Losses) No definition available.
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- Definition Time Deposits Placed And Other Short-Term Investments, Fair Value Disclosure No definition available.
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- Definition Accumulated unrealized gain (loss), after tax, 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of 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 investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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