Borrowings and Other Secured Financings (Other Secured Financings) (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Borrowings and Other Secured Financings | ||
| Secured financings with original maturities greater than one year | $ 6,772 | $ 8,685 |
| Secured financings with original maturities one year or less | 2,036 | 2,034 |
| Failed sales | 658 | 552 |
| Total other secured financings | $ 9,466 | $ 11,271 |