Fair Value Disclosures (Earnings Impact of Borrowings under the Fair Value Option) (Details) - Borrowings - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Fair Value Option Quantitative Disclosures | |||
| Earnings impact | $ 2,358 | $ (4,950) | $ (1,190) |
| Trading Revenues | |||
| Fair Value Option Quantitative Disclosures | |||
| Earnings impact | 2,679 | (4,507) | (707) |
| Interest Income (Expense) | |||
| Fair Value Option Quantitative Disclosures | |||
| Earnings impact | $ (321) | $ (443) | $ (483) |