Loans - Troubled Debt Restructurings (Details) (USD $) In Millions, unless otherwise specified						12 Months Ended					12 Months Ended					12 Months Ended			12 Months Ended						12 Months Ended	3 Months Ended	12 Months Ended					12 Months Ended								3 Months Ended		12 Months Ended								3 Months Ended		12 Months Ended								3 Months Ended			12 Months Ended								3 Months Ended		12 Months Ended						12 Months Ended							12 Months Ended																12 Months Ended														12 Months Ended				12 Months Ended				12 Months Ended				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Apr. 05, 2012 Mortgage Foreclosure Investigations and Litigation [Member] Global settlement on servicing and origination of mortgages [Member] Settlement of Litigation, Refinancing Relief Provided to Certain Borrowers [Member]	Apr. 05, 2012 Mortgage Foreclosure Investigations and Litigation [Member] Global settlement on servicing and origination of mortgages [Member] Settlement of Litigation, Additional Relief Provided to Certain Borrowers [Member]	Dec. 31, 2012 Credit Card Loan [Member] Days Past Due, 120 or More [Member] Financing Receivable, Policy, Current [Member]	Dec. 31, 2012 Credit Card Loan [Member] Days Past Due, 180 or More [Member] Financing Receivable, Policy, Previous [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card	Dec. 31, 2011 Consumer, Excluding Credit Card	Dec. 31, 2010 Consumer, Excluding Credit Card	Dec. 31, 2012 Consumer, Excluding Credit Card Minimum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Days Past Due, 30 or More [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Regulatory Guidance Regarding Chapter 7 Loans [Member] Days Past Due, 60 or More, with Notification of Bankruptcy Filing or Other Event [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Consumer Loan Excluding Credit Card [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Consumer Loan Excluding Credit Card [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Trial Modifications Approved On Or After July 1, 2010 [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Trial Modification [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Trial Modification [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Permanent Modification [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Permanent Modification [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Days Past Due, 60 or More, with Notification of Bankruptcy Filing or Other Event [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] loans	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Maximum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Minimum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Days Past Due, 30 or More [Member] Maximum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Days Past Due, 60 or Less [Member] Maximum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Residential Real Estate, Excluding Purchased Credit-Impaired [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Trial Modification [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Trial Modification [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Permanent Modification [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Permanent Modification [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] loans	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Senior Lien [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Trial Modification [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Trial Modification [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Permanent Modification [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Permanent Modification [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] loans	Dec. 31, 2012 Consumer, Excluding Credit Card Home Equity - Junior Lien [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Trial Modification [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Trial Modification [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Permanent Modification [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Permanent Modification [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] loans	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Prime Mortgages, Including Option ARMs [Member] Regulatory Guidance Regarding Prime, including Option ARM, mortgages [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Subprime Mortgages [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member] Trial Modification [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Subprime Mortgages [Member] Trial Modification [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member] Permanent Modification [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Subprime Mortgages [Member] Permanent Modification [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Subprime Mortgages [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] loans	Dec. 31, 2012 Consumer, Excluding Credit Card Subprime Mortgages [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Other Consumer [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Other Consumer [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Other Consumer [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Other Consumer [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Other Consumer [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Other Consumer [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Auto Loans [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Auto Loans [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Auto Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Auto Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Auto Loans [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Auto Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Auto Loans [Member] Regulatory Guidance Regarding Chapter 7 Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Business Banking Loans [Member] years	Dec. 31, 2011 Consumer, Excluding Credit Card Business Banking Loans [Member] years	Dec. 31, 2012 Consumer, Excluding Credit Card Business Banking Loans [Member] Maximum [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Business Banking Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Business Banking Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Business Banking Loans [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Business Banking Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Student and Other Loans [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Student and Other Loans [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Student and Other Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Student and Other Loans [Member] Days Past Due, 120 or More [Member]	Dec. 31, 2012 Consumer, Excluding Credit Card Student and Other Loans [Member] Nonaccrual [Member]	Dec. 31, 2011 Consumer, Excluding Credit Card Student and Other Loans [Member] Nonaccrual [Member]	Dec. 31, 2012 Credit Card	Dec. 31, 2011 Credit Card	Dec. 31, 2010 Credit Card	Dec. 31, 2012 Credit Card Credit Card Loan [Member]	Dec. 31, 2011 Credit Card Credit Card Loan [Member]	Dec. 31, 2012 Credit Card Credit Card Loan [Member] Credit Card Loan Modification Programs, Total [Member]	Dec. 31, 2011 Credit Card Credit Card Loan [Member] Credit Card Loan Modification Programs, Total [Member]	Dec. 31, 2012 Credit Card Credit Card Loan [Member] Short-Term Credit Card Loan Modification Programs [Member]	Dec. 31, 2011 Credit Card Credit Card Loan [Member] Short-Term Credit Card Loan Modification Programs [Member]	Dec. 31, 2012 Credit Card Credit Card Loan [Member] Long-Term Credit Card Loan Modification Programs [Member]	Dec. 31, 2011 Credit Card Credit Card Loan [Member] Long-Term Credit Card Loan Modification Programs [Member]	Dec. 31, 2012 Credit Card Credit Card Loan [Member] Days Past Due, 30 or More [Member]	Dec. 31, 2012 Credit Card Credit Card Loan [Member] Nonaccrual [Member]	Dec. 31, 2011 Credit Card Credit Card Loan [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale	Dec. 31, 2011 Wholesale	Dec. 31, 2010 Wholesale	Dec. 31, 2012 Wholesale Wholesale Loan [Member] years	Dec. 31, 2011 Wholesale Wholesale Loan [Member] years	Dec. 31, 2012 Wholesale Wholesale Loan [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Wholesale Loan [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Commercial and Industrial [Member]	Dec. 31, 2011 Wholesale Commercial and Industrial [Member]	Dec. 31, 2012 Wholesale Commercial and Industrial [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Commercial and Industrial [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Wholesale Real Estate [Member]	Dec. 31, 2011 Wholesale Wholesale Real Estate [Member]	Dec. 31, 2012 Wholesale Wholesale Real Estate [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Wholesale Real Estate [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Financial Institutions, Government Agencies and Other Wholesale [Member]	Dec. 31, 2011 Wholesale Financial Institutions, Government Agencies and Other Wholesale [Member]	Dec. 31, 2012 Wholesale Financial Institutions, Government Agencies and Other Wholesale [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Financial Institutions, Government Agencies and Other Wholesale [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Financial Institutions [Member]	Dec. 31, 2011 Wholesale Financial Institutions [Member]	Dec. 31, 2012 Wholesale Financial Institutions [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Financial Institutions [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Government Agencies [Member]	Dec. 31, 2011 Wholesale Government Agencies [Member]	Dec. 31, 2012 Wholesale Government Agencies [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Government Agencies [Member] Nonaccrual [Member]	Dec. 31, 2012 Wholesale Wholesale Other [Member]	Dec. 31, 2011 Wholesale Wholesale Other [Member]	Dec. 31, 2012 Wholesale Wholesale Other [Member] Nonaccrual [Member]	Dec. 31, 2011 Wholesale Wholesale Other [Member] Nonaccrual [Member]
Financing Receivable, Modifications [Line Items]
Number of Years Before Payment Default Under a Modified Loan																																																																																								1 year
Number of Payments Under New Terms to Recognize Interest on Cash Basis											6
Loans Modified in Troubled Debt Restructurings [Abstract]
Financing Receivable, Modifications, Recorded Investment																$ 13,245	$ 9,088		$ 474	$ 539	$ 12,771	$ 8,549									$ 1,600	$ 1,092	$ 335	$ 34	$ 50	$ 1,058	$ 285				$ 450	$ 1,223	$ 657	$ 5	$ 23	$ 1,218	$ 634				$ 448	$ 7,118	$ 4,877	$ 284	$ 276	$ 6,834	$ 4,601					$ 465	$ 3,812	$ 3,219	$ 151	$ 190	$ 3,661	$ 3,029				$ 245	$ 502	$ 503			$ 312	$ 291	$ 150	$ 88			$ 109	$ 38	$ 72	$ 352	$ 415				$ 203	$ 253										$ 4,189	$ 6,075													$ 696	$ 750	$ 636	$ 578	$ 575	$ 531	$ 522	$ 415	$ 99	$ 176	$ 92	$ 128	$ 22	$ 43	$ 22	$ 35
Loans and Leases Receivable, Impaired, Troubled Debt Restructuring, Funded Commitment To Lend																																																																																																																				46	147			44	147			0	0			2	0
Loans Receivable Held for Investment, Net of Deferred Income	726,835	718,997	685,498					292,620	308,427	327,464				292,620	308,427	151,896	163,660						8,460	6,530							1,700	19,385	21,765					931	495		450	48,000	56,035					2,277	792		440	76,256	76,196					3,445	3,462		500		8,255	9,664					1,807	1,781		357	80,987	79,221	589	621	714	881	49,913	47,426	7	7	163	118	51	18,883	17,652		138	153	481	694	12,191	14,143	444	461	70	69	127,993	132,175	135,524	127,993	132,175								1	1	306,222	278,395	222,510	306,222	278,395	1,434	2,398	109,865	94,215	708	889	60,740	54,684	520	886					36,227	38,219	8	37	9,544	7,819	0	16	89,846	83,458	198	570
Loss Contingency, Settlement Agreement, Consideration				500.0	3,700.0
Loan Modification Program, Fixed Payment Plan Period																																																																																																												60 months
Loans Modified in Troubled Debt Restructurings [Roll Forward]
Financing Receivable, Modifications, Recorded Investment, Beginning Balance																9,088	5,344		539		8,549										1,600	335	226	50		285					450	657	283	23		634					448	4,877	2,084	276		4,601						465	3,219	2,751	190		3,029					245	503	486			312	291	88	91			109	38	72	415	395				203	253										6,075														750	1,143	636	578	531	212	522	415	176	907	92	128	43	24	22	35
Financing Receivable, Modifications, New Troubled Debt Restructurings																5,507	4,807															835	138									711	518									2,918	3,268										1,043	883									249	249					145	54						104	195																	1,654	2,690	47	167	1,607	2,523							278	810			162	665			43	113			73	32
Financing Receivable, Impaired, Troubled Debt Restructuring, Increases to Existing Troubled Debt Restructurings																																																																																																																				183	112			183	96			0	16			0	0
Financing Receivable, Impaired, Troubled Debt Restructuring, Charge-offs Post-Modification																(376)	(446)															(31)	(15)									(2)	(78)									(135)	(119)										(208)	(234)									(18)	(16)					(9)	(5)						(9)	(11)																													(36)	(176)			(27)	(30)			(2)	(146)			(7)	0
Financing Receivable, Impaired, Troubled Debt Restructuring, Foreclosures and Other Liquidations																(277)	(201)															(5)	0									(21)	(11)									(138)	(108)										(113)	(82)									(1)	(3)					0	0						(1)	(3)
Financing Receivable, Impaired, Troubled Debt Restructuring, Principal Payments, Sales, and Other																(697)	(416)															(42)	(14)									(122)	(55)									(404)	(248)										(129)	(99)									(231)	(213)					(74)	(52)						(157)	(161)																													(479)	(1,139)			(274)	(412)			(118)	(714)			(87)	(13)
Financing Receivables, Impaired, Troubled Debt Restructuring, Performing Loans Restructured at Market Rates but No Longer Reported as TDRs																																																																																																																				44	152
Financing Receivable, Modifications, Recorded Investment, Ending Balance																13,245	9,088		474	539	12,771	8,549									1,600	1,092	335	34	50	1,058	285				450	1,223	657	5	23	1,218	634				448	7,118	4,877	284	276	6,834	4,601					465	3,812	3,219	151	190	3,661	3,029				245	502	503			312	291	150	88			109	38	72	352	415				203	253										4,189	6,075													696	750	636	578	575	531	522	415	99	176	92	128	22	43	22	35
Nature and Extent of Modifications [Abstract]
Mortgage Loans on Real Estate, Number of Loans																										37,300														9,000										20,700										3,800											3,800
Financing Receivable, Modifications, Number of Contract Modifications that Occurred																			3,207	4,060	30,822	24,699												410	654	4,385	1,006							528	778	7,430	9,142							1,101	898	9,043	9,579								1,168	1,730	9,964	4,972
Financing Receivable, Modifications, Percentage of Modifications that Occurred, Interest Rate Reductions																77.00%	75.00%															81.00%	76.00%									89.00%	95.00%									75.00%	54.00%										70.00%	79.00%
Financing Receivable, Modifications, Percentage of Modifications that Occurred, Term Or Payment Extension																57.00%	76.00%															49.00%	86.00%									76.00%	81.00%									61.00%	71.00%										45.00%	74.00%
Financing Receivable, Modifications, Percentage of Modifications that Occurred, Principal And Interest Deferred																16.00%	19.00%															8.00%	12.00%									19.00%	22.00%									21.00%	18.00%										12.00%	19.00%
Financing Receivable, Modifications, Percentage of Modifications that Occurred, Principal Forgiveness																30.00%	12.00%															12.00%	8.00%									22.00%	20.00%									30.00%	3.00%										43.00%	14.00%
Financing Receivable, Modifications, Percentage of Modifications that Occurred, Other																13.00%	35.00%															3.00%	27.00%									5.00%	7.00%									31.00%	68.00%										8.00%	26.00%
Percentage, Sum of Items by Type, May Exceed																100.00%
Financial Effects of Modifications and Redefaults [Abstract]
Financing Receivable, Modifications, Pre-Modification, Weighted-Average Interest Rate Of Loans With Rate Reductions																					6.56%	6.47%														7.14%	7.25%									5.40%	5.44%									6.12%	5.99%										7.78%	8.27%											12.64%	12.45%						7.33%	7.55%															15.67%	16.05%
Financing Receivable, Modifications, Post-Modification, Weighted-Average Interest Rate Of Loans With Rate Reductions																					3.62%	3.09%														4.56%	3.54%									1.89%	1.48%									3.57%	3.32%										4.09%	3.50%											4.83%	5.70%						5.49%	5.52%															5.19%	5.28%
Financing Receivable, Modifications, Pre-Modification, Weighted-Average Remaining Term																																																																																						1.4	1.4
Financing Receivable, Modifications, Pre-Modification, Weighted-Average Remaining Term of Financing Receivables With Term Or Payment Extensions																					23	24														19	18									20	21									25	25										23	23
Financing Receivable, Modifications, Average Term or Payment Extension Granted																																																																																																																				1.1	3.3
Financing Receivable, Modifications, Post-Modification, Weighted-Average Remaining Term																																																																																						2.4	2.6																													3.6	4.5
Financing Receivable, Modifications, Post-Modification, Weighted-Average Remaining Term of Financing Receivables With Term Or Payment Extensions																					34	35														28	30									32	34									36	35										32	34
Financing Receivable, Modifications, Weighted-Average Remaining Life																																				6										7										10											8
Financing Receivable, Impaired, Troubled Debt Restructuring, Write-down																					137	198														8	1									65	117									35	61										29	19
Financing Receivable, Modifications, Principal Deferred																					245	284														5	4									26	36									164	176										50	68
Financing Receivable, Modifications, Principal Forgiven																					770	142														23	1									58	62									318	24										371	55
Financing Receivable, Modifications, Subsequent Default Occurred, Number of Contracts																					4,156	4,154														374	201									1,436	1,170									920	1,041										1,426	1,742
Financing Receivable, Modifications, Subsequent Default Occurred, Recorded Investment																					$ 487	$ 628														$ 30	$ 17									$ 46	$ 47									$ 255	$ 319										$ 156	$ 245											$ 46							$ 42	$ 80															$ 309	$ 687													$ 56	$ 96
Financing Receivable, Trial Modifications Successfully Converted to Permanent Modifications																		85.00%
Rate of Default for Modified Loans, Estimated Weighted Average																											40.00%	10.00%								25.00%						20.00%														14.00%											24.00%																																			38.23%	35.47%
Period Past Due, Credit Analysis Factors, Charge off Criteria												30 days	60 days												90 days				30 days	60 days												180 days
Loans, Charge-off Criteria, Period Past Due						120 days	180 days																																																																																																							30 days
Financing Receivable, Modifications, Ratios [Abstract]
Percentage of Loans Thirty Plus Days Past Due to Total Retained Loans																4.28%	4.97%															3.60%	3.55%							19.00%		2.49%	2.68%							12.00%		3.97%	4.96%							45.00%			19.16%	21.51%							32.00%		1.58%	1.59%					1.25%	1.13%						2.12%	2.71%						2.12%	1.76%								2.10%	2.81%