Loans - Residential RealEstate - PCI Loans, FICO and LTV (Details 8b) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Purchased Credit Impaired [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 77,082	$ 86,073
Purchased Credit Impaired [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	10,121	11,802
Purchased Credit Impaired [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	12,114	15,246
Purchased Credit Impaired [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	13,516	14,584
Purchased Credit Impaired [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	10,945	12,375
Purchased Credit Impaired [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	10,091	10,491
Purchased Credit Impaired [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	7,680	8,367
Purchased Credit Impaired [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	6,522	6,551
Purchased Credit Impaired [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	6,093	6,657
PCI Home Equity [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	25,800	28,312
PCI Home Equity [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	5,463	6,289
PCI Home Equity [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,329	4,043
PCI Home Equity [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	5,569	6,053
PCI Home Equity [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,480	2,696
PCI Home Equity [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,839	3,995
PCI Home Equity [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,414	1,482
PCI Home Equity [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,618	2,641
PCI Home Equity [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,088	1,113
PCI Prime Mortgage [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	16,682	18,928
PCI Prime Mortgage [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,996	2,400
PCI Prime Mortgage [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,215	2,744
PCI Prime Mortgage [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,516	3,815
PCI Prime Mortgage [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,620	3,011
PCI Prime Mortgage [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,852	1,970
PCI Prime Mortgage [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,620	1,857
PCI Prime Mortgage [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,347	1,443
PCI Prime Mortgage [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,516	1,688
PCI Subprime Mortgage [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	7,437	8,042
PCI Subprime Mortgage [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	451	432
PCI Subprime Mortgage [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,940	2,129
PCI Subprime Mortgage [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	429	424
PCI Subprime Mortgage [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,585	1,663
PCI Subprime Mortgage [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	385	374
PCI Subprime Mortgage [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,302	1,477
PCI Subprime Mortgage [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	200	186
PCI Subprime Mortgage [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	1,145	1,357
PCI Option ARMs [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	27,163	30,791
PCI Option ARMs [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,211	2,681
PCI Option ARMs [Member] | Current Estimated LTV Greater Than 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,630	6,330
PCI Option ARMs [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,002	4,292
PCI Option ARMs [Member] | Current Estimated Ltv Between 101% And 125% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,260	5,005
PCI Option ARMs [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	4,015	4,152
PCI Option ARMs [Member] | Current Estimated LTV Between 80% To 100% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	3,344	3,551
PCI Option ARMs [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Equal to or greater than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,357	2,281
PCI Option ARMs [Member] | Current Estimated LTV Less Than 80% [Member] | Refreshed FICO Scores Less than 660 [Member]
Residential RealEstate - PCI Loans, by Class, by FICO and LTV [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	$ 2,344	$ 2,499