Reconciliation of the Beginning and Ending Balances for Fair Valued Assets and Liabilities Measured on a Recurring Basis Using Significant Unobservable Inputs (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Loans Held For Sale [Member] | Residential Mortgage, Loans Held For Sale [Member]
Included in earnings	$ 0		$ 1
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	(10)		(25)
Settlements	0		(1)
Transfers to other balance sheet line items	6		8
Transfers into Level 3	17		32
Transferred Out of Level 3 in The Fair Value Hierarchy	(3)		(4)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1		3		8
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0		0
Trading Account Assets [Member]
Included in earnings			117	[1]
OCI			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases			0
Sales			(20)
Settlements			0
Transfers to other balance sheet line items			222
Transfers into Level 3			0
Transferred Out of Level 3 in The Fair Value Hierarchy			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value			65		190
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income			11	[1],[2]
Trading Account Assets [Member] | Asset-backed Securities [Member]
Included in earnings	1	[3]	1
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	(7)		0
Settlements	0		0
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0		6		5
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0	[3],[4]	1
Trading Account Assets [Member] | Other Debt Obligations [Member]
Included in earnings			0
OCI			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases			0
Sales			0
Settlements			(1)
Transfers to other balance sheet line items			0
Transfers into Level 3			0
Transferred Out of Level 3 in The Fair Value Hierarchy			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value			0		1
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income			0
Trading Account Assets [Member] | Collateralized Debt Obligations [Member]
Included in earnings	11	[3]	23	[1]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	(65)		(20)
Settlements	0		(1)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0		54		52
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0	[3],[4]	15	[1],[2]
Trading Assets [Member]
Included in earnings	264	[3]
OCI	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0
Sales	(72)
Settlements	(8)
Transfers to other balance sheet line items	245
Transfers into Level 3	0
Transferred Out of Level 3 in The Fair Value Hierarchy	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	20		65
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0	[3],[4]
Trading Assets [Member] | Derivative contracts, net [Member]
Included in earnings	252	[3]	93	[3]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	8		2
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	20		5		132
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0	[3],[4]	(5)	[3],[4]
Available-for-sale Securities [Member]
Included in earnings	(3)	[5]	(1)	[6]
OCI	4		1	[7]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	360		204
Sales	(20)		(6)
Settlements	(354)		(159)
Transfers to other balance sheet line items	(6)		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	946		953		914
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	(1)	[4],[5]	(1)	[2],[6]
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member]
Included in earnings	(2)		0
OCI	0		2
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	(20)		(6)
Settlements	0		(8)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	12		34		46
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0		0
Available-for-sale Securities [Member] | Asset-backed Securities [Member]
Included in earnings	0	[5]	(1)
OCI	2		4	[7]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(2)		(3)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	21		21		21
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0	[4],[5]	(1)
Available-for-sale Securities [Member] | Other Debt Obligations [Member]
Included in earnings	0		0
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		4
Sales	0		0
Settlements	0		(4)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	5		5		5
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0		0
Available-for-sale Securities [Member] | Equity Securities [Member]
Included in earnings	0		0
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	360		200
Sales	0		0
Settlements	(320)		(94)
Transfers to other balance sheet line items	(6)		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	785		739		633
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	0		0
Available-for-sale Securities [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Included in earnings	(1)		0	[6]
OCI	2		(5)	[7]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(32)		(50)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	123		154		209
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	(1)		0	[2],[6]
Loans Held For Investment [Member]
Included in earnings	12	[8]	(5)	[9]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(45)		(55)
Transfers to other balance sheet line items	(1)		17
Transfers into Level 3	2		0
Transferred Out of Level 3 in The Fair Value Hierarchy	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	272		302		379
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Included in Other Income	9	[4],[8]	(11)	[2],[9]
Other Liabilities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(3)		(4)
Transfers to other balance sheet line items	0		0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liabilities Transfers Into Level 3	0		0
Fair Value Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liabilities Transfers Out Of Level 3	0		0
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0	[10],[4]	(1)	[10],[4]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	27		26		31
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	4	[10]	(1)	[10]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss)	0		0
Interest Rate Lock Commitments [Member]
Transferred Out of Level 3 in The Fair Value Hierarchy	(245)		(222)
Interest Rate Lock Commitments [Member] | Trading Assets [Member] | Derivative contracts, net [Member]
Transfers to other balance sheet line items	$ 245		$ 222

[1] December 31, 2013.2 Amounts included in earnings are net of issuances, fair value changes, and expirations and are recognized in mortgage production related inco

[2] 1 Change in unrealized gains/(losses) included in earnings for the period related to financial assets still held at

[3] 2 Amounts included in earnings are net of issuances, fair value changes, and expirations and are recognized in mortgage production related income.

[4] 1 Change in unrealized gains/(losses) included in earnings during the period related to financial assets still held at December 31, 2014.

[5] 3 Amounts included in earnings are recognized in trading income.

[6] e.3 Amounts included in earnings are recognized in trading inco

[7] s.6 Amounts are generally included in mortgage production related income; however, the mark on certain fair value loans is included in trading inco

[8] 4 Amounts included in earnings are recognized in net securities (losses)/gains.

[9] e.4 Amounts included in earnings are recognized in net securities (losses)/gai

[10] 5 Amount recognized in OCI is recognized in change in unrealized gains/(losses) on AFS securities.