Securities - Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
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| Schedule of Available-for-sale Securities [Line Items] | |||||
| Fair Value | $ 239,048 | $ 239,048 | $ 302,631 | ||
| Unrealized mark-to-market net gains (losses) | (106) | $ 124 | (37) | $ 323 | |
| Realized net gains (losses) | 114 | $ (11) | 123 | $ (129) | |
| Other assets | |||||
| Schedule of Available-for-sale Securities [Line Items] | |||||
| Equity securities, fair value | 947 | 947 | |||
| Equity securities, cost | 252 | 252 | |||
| Time Deposits Placed and Other Short-term Investments | |||||
| Schedule of Available-for-sale Securities [Line Items] | |||||
| Equity securities, fair value | 1,500 | 1,500 | |||
| Nonperforming Financing Receivable | |||||
| Schedule of Available-for-sale Securities [Line Items] | |||||
| Fair Value | 71 | 71 | $ 99 | ||
| Debt securities | |||||
| Schedule of Available-for-sale Securities [Line Items] | |||||
| Shareholders’ equity | (6,400) | (6,400) | |||
| Accumulated other comprehensive income tax expense (benefit) | $ (2,100) | $ (2,100) | |||
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- Definition Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Tax No definition available.
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- Definition Equity Securities, FV-NI No definition available.
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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 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 Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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