Fair Value (Fair Value Measurement - Reconciliation of Level 3 Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance	$ 115	$ 1,461	$ 1,151	$ 3,797
Net realized/unrealized gains (losses) included in earnings, Assets	55	(212)	(93)	(199)
Net realized/unrealized gains (losses) included in other comprehensive income, Assets	0	1	0	2
Purchases, Assets	0	0	0	12
Sales, Assets	0	(11)	(911)	(256)
Issuances, Assets	0	50	60	167
Settlements, Assets	8	(41)	(29)	(495)
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				(1,780)
Fair Value, Assets, Ending balance	178	1,248	178	1,248
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	47	(264)	38	(638)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liabilities, Beginning balance				(859)
Net realized/unrealized gains (losses) included in earnings, Liabilities				(115)
Net realized/unrealized gains (losses) included in other comprehensive income, Liabilities				0
Purchases, Liabilities				(11)
Sales, Liabilities				0
Issuances, Liabilities				0
Settlements, Liabilities				399
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Liabilities				586
Fair Value, Liabilities, Ending balance		0		0
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)				(62)
On-Balance Sheet Securitization Debt [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liabilities, Beginning balance				(830)
Net realized/unrealized gains (losses) included in earnings, Liabilities				(115)
Net realized/unrealized gains (losses) included in other comprehensive income, Liabilities				0
Purchases, Liabilities				0
Sales, Liabilities				0
Issuances, Liabilities				0
Settlements, Liabilities				389
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Liabilities				556
Fair Value, Liabilities, Ending balance		0		0
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)				(62)
Loan repurchase liabilities [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liabilities, Beginning balance				(29)
Net realized/unrealized gains (losses) included in earnings, Liabilities				0
Net realized/unrealized gains (losses) included in other comprehensive income, Liabilities				0
Purchases, Liabilities				(11)
Sales, Liabilities				0
Issuances, Liabilities				0
Settlements, Liabilities				10
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Liabilities				30
Fair Value, Liabilities, Ending balance		0		0
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)				0
Residential Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance				33
Net realized/unrealized gains (losses) included in earnings, Assets				2
Net realized/unrealized gains (losses) included in other comprehensive income, Assets				0
Purchases, Assets				0
Sales, Assets				0
Issuances, Assets				0
Settlements, Assets				(4)
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				(31)
Fair Value, Assets, Ending balance		0		0
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)				4
Asset-backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance		63		62
Net realized/unrealized gains (losses) included in earnings, Assets		4		4
Net realized/unrealized gains (losses) included in other comprehensive income, Assets		1		2
Purchases, Assets		0		0
Sales, Assets		(11)		(11)
Issuances, Assets		0		0
Settlements, Assets		0		0
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				0
Fair Value, Assets, Ending balance		57		57
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)		0		0
Mortgage Loans Held-For-Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance				30
Net realized/unrealized gains (losses) included in earnings, Assets				0
Net realized/unrealized gains (losses) included in other comprehensive income, Assets				0
Purchases, Assets				12
Sales, Assets				0
Issuances, Assets				0
Settlements, Assets				(11)
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				(31)
Fair Value, Assets, Ending balance		0		0
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)				0
Consumer Mortgage Finance Receivables And Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance				835
Net realized/unrealized gains (losses) included in earnings, Assets				121
Net realized/unrealized gains (losses) included in other comprehensive income, Assets				0
Purchases, Assets				0
Sales, Assets				(245)
Issuances, Assets				0
Settlements, Assets				(124)
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				(587)
Fair Value, Assets, Ending balance		0		0
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)				51
Mortgage Servicing Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance		1,105	952	2,519
Net realized/unrealized gains (losses) included in earnings, Assets	0	(253)	(101)	(538)
Net realized/unrealized gains (losses) included in other comprehensive income, Assets		0	0	0
Purchases, Assets		0	0	0
Sales, Assets		0	(911)	0
Issuances, Assets		50	60	167
Settlements, Assets		0	0	0
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				(1,130)
Fair Value, Assets, Ending balance	0	902	0	902
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)		(253)	0	(654)
Retained Interest [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets, Beginning balance	124	193	154	231
Net realized/unrealized gains (losses) included in earnings, Assets	8	11	19	38
Net realized/unrealized gains (losses) included in other comprehensive income, Assets	0	0	0	0
Purchases, Assets	0	0	0	0
Sales, Assets	0	0	0	0
Issuances, Assets	0	0	0	0
Settlements, Assets	(11)	(39)	(52)	(104)
Transfers out of Level 3 Due to Deconsolidation or Discontinued Operations, Assets				0
Fair Value, Assets, Ending balance	121	165	121	165
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0	0	0	0
Derivative Financial Instruments, Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Net Derivative Asset (Liability), Beginning balance	(9)	100	45	87
Gain (Loss) Included in Earnings, Net Derivative Asset (Liability)	47	26	(11)	290
Gain (Loss) Included in Other Comprehensive Income (Loss), Net Derivative Asset (Liability)	0	0	0	0
Purchases, Net Derivative Asset (Liability)	0	0	0	0
Sales, Net Derivative Asset (Liability)	0	0	0	0
Issuances, Net Derivative Asset (Liability)	0	0	0	0
Settlements, Net Derivative Asset (Liability)	19	(2)	23	(252)
Transfers out of Level 3, Net Derivative Asset (Liability)				(1)
Fair Value, Net Derivative Asset (Liability), Ending balance	57	124	57	124
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	47	(11)	38	(39)
Interest Rate Contract [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Net Derivative Asset (Liability), Beginning balance		93	47	71
Gain (Loss) Included in Earnings, Net Derivative Asset (Liability)		53	(51)	326
Gain (Loss) Included in Other Comprehensive Income (Loss), Net Derivative Asset (Liability)		0	0	0
Purchases, Net Derivative Asset (Liability)		0	0	0
Sales, Net Derivative Asset (Liability)		0	0	0
Issuances, Net Derivative Asset (Liability)		0	0	0
Settlements, Net Derivative Asset (Liability)		(2)	4	(252)
Transfers out of Level 3, Net Derivative Asset (Liability)				(1)
Fair Value, Net Derivative Asset (Liability), Ending balance	0	144	0	144
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)		16	0	10
Foreign Exchange Contract [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Net Derivative Asset (Liability), Beginning balance	(9)	7	(2)	16
Gain (Loss) Included in Earnings, Net Derivative Asset (Liability)	47	(27)	40	(36)
Gain (Loss) Included in Other Comprehensive Income (Loss), Net Derivative Asset (Liability)	0	0	0	0
Purchases, Net Derivative Asset (Liability)	0	0	0	0
Sales, Net Derivative Asset (Liability)	0	0	0	0
Issuances, Net Derivative Asset (Liability)	0	0	0	0
Settlements, Net Derivative Asset (Liability)	19	0	19	0
Transfers out of Level 3, Net Derivative Asset (Liability)				0
Fair Value, Net Derivative Asset (Liability), Ending balance	57	(20)	57	(20)
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	47	(27)	38	(49)
Fair Value, Inputs, Level 3 [Member] | Mortgage Servicing Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Net realized/unrealized gains (losses) included in earnings, Assets		$ (253)	$ (101)	$ (654)