Loans - Residential RealEstate - PCI Loans, Geographic (Details 8c) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Purchased Credit Impaired [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 74,492	$ 86,073
Purchased Credit Impaired [Member] | California [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	39,438	46,004
Purchased Credit Impaired [Member] | New York [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,454	4,866
Purchased Credit Impaired [Member] | Florida [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	7,585	8,936
Purchased Credit Impaired [Member] | Illinois [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,182	2,387
Purchased Credit Impaired [Member] | Texas [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,168	1,309
Purchased Credit Impaired [Member] | New Jersey [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,182	2,406
Purchased Credit Impaired [Member] | Arizona [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,210	1,591
Purchased Credit Impaired [Member] | Washington [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,565	2,909
Purchased Credit Impaired [Member] | Ohio [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	336	382
Purchased Credit Impaired [Member] | Michigan [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	775	933
Purchased Credit Impaired [Member] | All Other States [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	12,597	14,350
PCI Home Equity [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	25,064	28,312
PCI Home Equity [Member] | California [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	15,091	17,012
PCI Home Equity [Member] | New York [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,179	1,316
PCI Home Equity [Member] | Florida [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,307	2,595
PCI Home Equity [Member] | Illinois [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	558	627
PCI Home Equity [Member] | Texas [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	455	525
PCI Home Equity [Member] | New Jersey [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	471	540
PCI Home Equity [Member] | Arizona [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	468	539
PCI Home Equity [Member] | Washington [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,368	1,535
PCI Home Equity [Member] | Ohio [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	32	38
PCI Home Equity [Member] | Michigan [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	81	95
PCI Home Equity [Member] | All Other States [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,054	3,490
PCI Option ARMs [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	26,139	30,791
PCI Option ARMs [Member] | California [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	13,565	16,130
PCI Option ARMs [Member] | New York [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,548	1,703
PCI Option ARMs [Member] | Florida [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,201	3,916
PCI Option ARMs [Member] | Illinois [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	702	760
PCI Option ARMs [Member] | Texas [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	140	155
PCI Option ARMs [Member] | New Jersey [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	969	1,064
PCI Option ARMs [Member] | Arizona [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	362	528
PCI Option ARMs [Member] | Washington [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	649	745
PCI Option ARMs [Member] | Ohio [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	111	131
PCI Option ARMs [Member] | Michigan [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	268	345
PCI Option ARMs [Member] | All Other States [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,624	5,314
PCI Prime Mortgage [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	16,060	18,928
PCI Prime Mortgage [Member] | California [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	9,121	10,891
PCI Prime Mortgage [Member] | New York [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,018	1,111
PCI Prime Mortgage [Member] | Florida [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,265	1,519
PCI Prime Mortgage [Member] | Illinois [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	511	562
PCI Prime Mortgage [Member] | Texas [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	168	194
PCI Prime Mortgage [Member] | New Jersey [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	445	486
PCI Prime Mortgage [Member] | Arizona [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	254	359
PCI Prime Mortgage [Member] | Washington [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	388	451
PCI Prime Mortgage [Member] | Ohio [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	79	91
PCI Prime Mortgage [Member] | Michigan [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	239	279
PCI Prime Mortgage [Member] | All Other States [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,572	2,985
PCI Subprime Mortgage [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	7,229	8,042
PCI Subprime Mortgage [Member] | California [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,661	1,971
PCI Subprime Mortgage [Member] | New York [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	709	736
PCI Subprime Mortgage [Member] | Florida [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	812	906
PCI Subprime Mortgage [Member] | Illinois [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	411	438
PCI Subprime Mortgage [Member] | Texas [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	405	435
PCI Subprime Mortgage [Member] | New Jersey [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	297	316
PCI Subprime Mortgage [Member] | Arizona [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	126	165
PCI Subprime Mortgage [Member] | Washington [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	160	178
PCI Subprime Mortgage [Member] | Ohio [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	114	122
PCI Subprime Mortgage [Member] | Michigan [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	187	214
PCI Subprime Mortgage [Member] | All Other States [Member]
Residential Real Estate PCI Loans by Class by Geographic Region [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 2,347	$ 2,561