Fair Value Of Financial Instruments (Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) (Fair Value Inputs Level 3 [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	$ 3,532		$ 4,188
Realized gains/(losses), assets	(9)		(71)
Unrealized gains/(losses) included in earnings, assets	342		106
Unrealized gains/(losses) included in OCI, assets	36		123
Foreign exchange recognized in OCI or earnings, assets	0		1
Purchases, assets	75		74
Issuances, assets	0		0
Settlements, assets	(1,272)		(438)
Sales, assets	(374)		(582)
Transfers into level 3, assets	218	[1]	288	[1]
Transfers out of level 3, assets	(196)	[1]	(157)	[1]
Ending balance, fair value assets	2,352		3,532
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	350		151
Beginning balance, fair value liabilities	5,039		7,938
Realized gains/(losses), liabilities	1,548		407
Unrealized gains/(losses included in earnings, liabilities	(1,577)		(1,403)
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	9		3
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	(1,825)		(846)
Sales, liabilities	(1,076)	[2]	(1,065)	[2]
Transfers into Level 3, liabilities	185	[1]	5	[1]
Transfers out of Level 3, liabilities	(2)	[1]	0	[1]
Ending balance, fair value liabilities	2,301		5,039
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	189		(499)
Loans Receivable [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	1,881		2,046
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	180		114
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(275)		(277)
Sales, assets	(174)		(2)
Transfers into level 3, assets	0	[1]	0	[1]
Transfers out of level 3, assets	0	[1]	0	[1]
Ending balance, fair value assets	1,612		1,881
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	166		114
Loan Repurchase Commitments [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	1,086		1,077
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	172		9
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(899)		0
Sales, assets	0		0
Transfers into level 3, assets	0	[1]	0	[1]
Transfers out of level 3, assets	0	[1]	0	[1]
Ending balance, fair value assets	359		1,086
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	172		9
State and municipal bonds [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	103		28
Realized gains/(losses), assets	2		0
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	(1)		(1)
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(5)		(7)
Sales, assets	(13)		0
Transfers into level 3, assets	42	[1]	83	[1]
Transfers out of level 3, assets	(109)	[1]	0	[1]
Ending balance, fair value assets	19		103
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Foreign Government Debt [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	3		11
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		1
Purchases, assets	10		21
Issuances, assets	0		0
Settlements, assets	(16)		(29)
Sales, assets	0		(4)
Transfers into level 3, assets	18	[1]	3	[1]
Transfers out of level 3, assets	(3)	[1]	0	[1]
Ending balance, fair value assets	12		3
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Corporate Obligations [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	76		207
Realized gains/(losses), assets	(5)		(15)
Unrealized gains/(losses) included in earnings, assets	7		10
Unrealized gains/(losses) included in OCI, assets	13		27
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	1		17
Issuances, assets	0		0
Settlements, assets	(16)		(29)
Sales, assets	(28)		(141)
Transfers into level 3, assets	1	[1]	25	[1]
Transfers out of level 3, assets	(1)	[1]	(25)	[1]
Ending balance, fair value assets	48		76
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	7		9
Corporate Obligations [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	78		69
Realized gains/(losses), assets	(4)		0
Unrealized gains/(losses) included in earnings, assets	(7)		(19)
Unrealized gains/(losses) included in OCI, assets	6		(6)
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		27
Issuances, assets	0		0
Settlements, assets	(4)		(5)
Sales, assets	(24)		0
Transfers into level 3, assets	3	[1]	15	[1]
Transfers out of level 3, assets	0	[1]	(3)	[1]
Ending balance, fair value assets	48		78
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		3
Residential Mortgage Backed Agency [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	0		0
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(1)		0
Sales, assets	0		0
Transfers into level 3, assets	20	[1]	4	[1]
Transfers out of level 3, assets	(19)	[1]	(4)	[1]
Ending balance, fair value assets	0		0
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Residential Mortgage Backed Non Agency [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	4		17
Realized gains/(losses), assets	0		(1)
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(2)		(13)
Sales, assets	0		(5)
Transfers into level 3, assets	5	[1]	31	[1]
Transfers out of level 3, assets	(1)	[1]	(25)	[1]
Ending balance, fair value assets	6		4
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Residential Mortgage Backed Non Agency [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	6		21
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	6		6
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(7)		(7)
Sales, assets	0		(16)
Transfers into level 3, assets	3	[1]	6	[1]
Transfers out of level 3, assets	(4)	[1]	(4)	[1]
Ending balance, fair value assets	4		6
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		3
Commercial Mortgage Backed Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	28		32
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	4		6
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		1
Issuances, assets	0		0
Settlements, assets	(1)		0
Sales, assets	(19)		0
Transfers into level 3, assets	3	[1]	1	[1]
Transfers out of level 3, assets	(1)	[1]	(12)	[1]
Ending balance, fair value assets	14		28
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Commercial Mortgage Backed Securities [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	7		22
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	0		4
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	0		(4)
Sales, assets	(24)		(9)
Transfers into level 3, assets	20	[1]	5	[1]
Transfers out of level 3, assets	0	[1]	(11)	[1]
Ending balance, fair value assets	3		7
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	1		1
Collateralized Debt Obligations [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	31		60
Realized gains/(losses), assets	(2)		(9)
Unrealized gains/(losses) included in earnings, assets	1		0
Unrealized gains/(losses) included in OCI, assets	12		20
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	61		1
Issuances, assets	0		0
Settlements, assets	(17)		(15)
Sales, assets	(5)		(10)
Transfers into level 3, assets	31	[1]	18	[1]
Transfers out of level 3, assets	(30)	[1]	(34)	[1]
Ending balance, fair value assets	82		31
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	1		0
Collateralized Debt Obligations [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	125		203
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	(8)		(25)
Unrealized gains/(losses) included in OCI, assets	5		2
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	(5)		(12)
Sales, assets	(85)		(74)
Transfers into level 3, assets	4	[1]	56	[1]
Transfers out of level 3, assets	(14)	[1]	(25)	[1]
Ending balance, fair value assets	22		125
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	1		5
Other Asset Backed [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	26		317
Realized gains/(losses), assets	0		(46)
Unrealized gains/(losses) included in earnings, assets	0		0
Unrealized gains/(losses) included in OCI, assets	(3)		73
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	3		3
Issuances, assets	0		0
Settlements, assets	(10)		(29)
Sales, assets	0		(285)
Transfers into level 3, assets	47	[1]	4	[1]
Transfers out of level 3, assets	(5)	[1]	(11)	[1]
Ending balance, fair value assets	58		26
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	0		0
Other Asset Backed [Member] | Variable Interest Entity Primary Beneficiary [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	64		67
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	(9)		6
Unrealized gains/(losses) included in OCI, assets	0		0
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		4
Issuances, assets	0		0
Settlements, assets	(14)		(11)
Sales, assets	(2)		(36)
Transfers into level 3, assets	21	[1]	34	[1]
Transfers out of level 3, assets	(6)	[1]	0	[1]
Ending balance, fair value assets	54		64
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	2		7
Medium Term Notes [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	165		165
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	29		(3)
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	9		3
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	0		0
Sales, liabilities	0		0
Transfers into Level 3, liabilities	0	[1]	0	[1]
Transfers out of Level 3, liabilities	0	[1]	0	[1]
Ending balance, fair value liabilities	203		165
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	38		(3)
Credit Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	2,921		4,790
Realized gains/(losses), liabilities	1,548		407
Unrealized gains/(losses included in earnings, liabilities	(1,778)		(1,869)
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	(1,548)		(407)
Sales, liabilities	0		0
Transfers into Level 3, liabilities	4	[1]	0	[1]
Transfers out of Level 3, liabilities	0	[1]	0	[1]
Ending balance, fair value liabilities	1,147		2,921
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	87		(927)
Credit Derivatives [Member] | Liabilities Of Consolidated Vies [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	0		80
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	0		2
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	0		0
Sales, liabilities	0		(82)
Transfers into Level 3, liabilities	0	[1]	0	[1]
Transfers out of Level 3, liabilities	0	[1]	0	[1]
Ending balance, fair value liabilities	0		0
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	0		0
Interest Rate Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	(1)		(3)
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	2		(2)
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	0		0
Sales, liabilities	0		0
Transfers into Level 3, liabilities	0	[1]	4	[1]
Transfers out of Level 3, liabilities	(1)	[1]	0	[1]
Ending balance, fair value liabilities	0		(1)
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	(18)		18
Variable Interest Entity Notes [Member] | Liabilities Of Consolidated Vies [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	1,932		2,889
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	180		465
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	(277)		(439)
Sales, liabilities	(1,076)		(983)
Transfers into Level 3, liabilities	181	[1]	0	[1]
Transfers out of Level 3, liabilities	0	[1]	0	[1]
Ending balance, fair value liabilities	940		1,932
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	92		409
Currency Derivatives [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	1		0
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	0		0
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	0		0
Sales, liabilities	0		0
Transfers into Level 3, liabilities	0	[1]	1	[1]
Transfers out of Level 3, liabilities	(1)	[1]	0	[1]
Ending balance, fair value liabilities	0		1
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	0		0
Currency Derivatives [Member] | Liabilities Of Consolidated Vies [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value liabilities	21		17
Realized gains/(losses), liabilities	0		0
Unrealized gains/(losses included in earnings, liabilities	(10)		4
Unrealized gains/(losses) included in OCI, liabilities	0		0
Foreign exchange recognized in OCI or earnings, liabilities	0		0
Purchases, liabilities	0		0
Issuances, liabilities	0		0
Settlements, liabilities	0		0
Sales, liabilities	0		0
Transfers into Level 3, liabilities	0	[1]	0	[1]
Transfers out of Level 3, liabilities	0	[1]	0	[1]
Ending balance, fair value liabilities	11		21
Change in unrealized gains/(losses) for the period included in earnings for liabilities still held, liabilities	(10)		4
Perpetual Debt And Equity Securities [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance, fair value assets	14		11
Realized gains/(losses), assets	0		0
Unrealized gains/(losses) included in earnings, assets	0		1
Unrealized gains/(losses) included in OCI, assets	0		2
Foreign exchange recognized in OCI or earnings, assets	0		0
Purchases, assets	0		0
Issuances, assets	0		0
Settlements, assets	0		0
Sales, assets	0		0
Transfers into level 3, assets	0	[1]	3	[1]
Transfers out of level 3, assets	(3)	[1]	(3)	[1]
Ending balance, fair value assets	11		14
Change in unrealized gains/(losses) for the period included in earnings for assets still held, assets	$ 0		$ 0

[1] (1) - Transferred in and out at the end of the period.

[2] Primarily relates to the deconsolidation of VIEs.