|
Commitments and Contingencies - Credit Extension Commitments (Details) (USD $)
|
Jun. 30, 2013
|
Mar. 31, 2013
|
Dec. 31, 2012
|
Jun. 30, 2012
|
Mar. 31, 2012
|
Dec. 31, 2011
|
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Credit Extension Commitments [Abstract] | ||||||||||||
| Legally Binding Unfunded Commitments Syndicated | $ 22,100,000,000 | $ 23,900,000,000 | ||||||||||
| Carrying Amount Credit Extension Commitments Syndicated | 493,000,000 | 534,000,000 | ||||||||||
| Deferred revenue related to binding unfunded lending commitments | 19,000,000 | 21,000,000 | ||||||||||
| Other Liabilities Reserve For Unfunded Lending Commitments | 474,000,000 | 486,000,000 | 513,000,000 | 574,000,000 | 651,000,000 | 714,000,000 | ||||||
| Notional Amount Of Credit Extension Commitments Under Fair Value Option | 15,900,000,000 | 18,300,000,000 | ||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 504,128,000,000 | 530,383,000,000 | ||||||||||
| Expire After One Year Through Three Years | 119,537,000,000 | 108,926,000,000 | ||||||||||
| Expire After Three Years Through Five Years | 158,542,000,000 | 157,253,000,000 | ||||||||||
| Expire After Five Years | 42,072,000,000 | 47,095,000,000 | ||||||||||
| Notional Amount Of Credit Extension Commitments | 824,279,000,000 | 843,657,000,000 | ||||||||||
|
External Credit Rating, Investment Grade [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Notional amount of Sblcs and financial guarantees | 29,800,000,000 | 31,500,000,000 | ||||||||||
|
External Credit Rating, Non Investment Grade [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Notional amount of Sblcs and financial guarantees | 10,100,000,000 | 11,600,000,000 | ||||||||||
|
Legally Binding Commitments [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 121,530,000,000 | 132,521,000,000 | ||||||||||
| Expire After One Year Through Three Years | 119,537,000,000 | 108,926,000,000 | ||||||||||
| Expire After Three Years Through Five Years | 158,542,000,000 | 157,253,000,000 | ||||||||||
| Expire After Five Years | 42,072,000,000 | 47,095,000,000 | ||||||||||
| Notional Amount Of Credit Extension Commitments | 441,681,000,000 | 445,795,000,000 | ||||||||||
|
Loan Commitments [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 92,984,000,000 | 103,791,000,000 | ||||||||||
| Expire After One Year Through Three Years | 93,336,000,000 | 83,885,000,000 | ||||||||||
| Expire After Three Years Through Five Years | 132,788,000,000 | 130,805,000,000 | ||||||||||
| Expire After Five Years | 21,120,000,000 | 19,942,000,000 | ||||||||||
| Notional Amount Of Credit Extension Commitments | 340,228,000,000 | 338,423,000,000 | ||||||||||
|
Home Equity [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 3,116,000,000 | 2,134,000,000 | ||||||||||
| Expire After One Year Through Three Years | 15,907,000,000 | 13,584,000,000 | ||||||||||
| Expire After Three Years Through Five Years | 23,295,000,000 | 23,344,000,000 | ||||||||||
| Expire After Five Years | 16,112,000,000 | 21,856,000,000 | ||||||||||
| Notional Amount Of Credit Extension Commitments | 58,430,000,000 | 60,918,000,000 | ||||||||||
|
Financial Standby Letter Of Credit And Financial Guarantee [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 23,126,000,000 | [1] | 24,593,000,000 | [1] | ||||||||
| Expire After One Year Through Three Years | 10,239,000,000 | [1] | 11,387,000,000 | [1] | ||||||||
| Expire After Three Years Through Five Years | 2,457,000,000 | [1] | 3,094,000,000 | [1] | ||||||||
| Expire After Five Years | 4,005,000,000 | [1] | 4,751,000,000 | [1] | ||||||||
| Notional Amount Of Credit Extension Commitments | 39,827,000,000 | [1] | 43,825,000,000 | [1] | ||||||||
|
Financial Standby Letter Of Credit And Financial Guarantee [Member] | Consumer Letter of Credit [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Notional Amount Of Credit Extension Commitments | 10,000,000 | 669,000,000 | ||||||||||
|
Letter of Credit [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 2,304,000,000 | 2,003,000,000 | ||||||||||
| Expire After One Year Through Three Years | 55,000,000 | 70,000,000 | ||||||||||
| Expire After Three Years Through Five Years | 2,000,000 | 10,000,000 | ||||||||||
| Expire After Five Years | 835,000,000 | 546,000,000 | ||||||||||
| Notional Amount Of Credit Extension Commitments | 3,196,000,000 | 2,629,000,000 | ||||||||||
|
Credit Card Lines [Member]
|
||||||||||||
| Notional Amount of Credit Extension Commitments [Abstract] | ||||||||||||
| Expire in One Year or Less | 382,598,000,000 | [2] | 397,862,000,000 | [2] | ||||||||
| Notional Amount Of Credit Extension Commitments | 382,598,000,000 | [2] | 397,862,000,000 | [2] | ||||||||
|
Unfunded loan commitments [Member]
|
||||||||||||
| Credit Extension Commitments [Abstract] | ||||||||||||
| Fair Value Carrying Amount Liabilities | $ 486,000,000 | $ 528,000,000 | ||||||||||
|
||||||||||||