|
Investment Securities (Parenthetical) (Details) (USD $)
In Millions, unless otherwise specified |
Sep. 30, 2012
|
Dec. 31, 2011
|
|---|---|---|
| Investment [Line Items] | ||
| Investment securities (Note 3) | $ 48,695 | $ 47,359 |
| OTTI previously recognized through OCI on securities held | (137) | |
|
Residential Mortgage Backed Securities [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
|
||
| Investment [Line Items] | ||
| Investment securities (Note 3) | 895 | |
|
Residential Mortgage Backed Securities [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
|
||
| Investment [Line Items] | ||
| Investment securities (Note 3) | $ 1,529 |