Long-Term Borrowings and Other Secured Financings (Other Secured Financings) (Details) - USD ($) $ in Millions |
Mar. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Components of other secured financings | ||
| Secured financings with original maturities greater than one year | $ 7,551 | $ 7,629 |
| Secured financings with original maturities one year or less | 1,373 | 1,435 |
| Failed sales | 392 | 400 |
| Total other secured financings | $ 9,316 | $ 9,464 |