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, 2012		Dec. 31, 2011
Derivative Financial Instruments, Liabilities [Member]
Beginning balance	$ (189)		$ (145)
Included in earnings	(304)	[1]	2	[2]
OCI	194	[3]	(46)	[4]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	0		0
Sales	0		0
Settlements	299		0
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
Fair value, ending balance	0		(189)
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		2	[2],[5]
Trading Account Assets [Member]
Beginning balance	49		209
Included in earnings	11	[2]	49	[2]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		6
Sales	0		(57)
Settlements	(2)		(138)
Transfers to other balance sheet line items	0		20
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	58		49
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	9	[2],[6]	10	[2],[5]
Trading Account Assets [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Beginning balance	1		6
Included in earnings	0		1
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		(5)
Settlements	0		(1)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	1		1
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		(1)	[5]
Trading Account Assets [Member] | Collateralized Debt Obligations [Member]
Beginning balance	43		53
Included in earnings	11		26	[7]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		6
Sales	0		(21)
Settlements	(2)		(1)
Transfers to other balance sheet line items	0		20
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	52		43
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	9	[6]	9	[5],[7]
Trading Account Assets [Member] | Asset-backed Securities [Member]
Beginning balance	5		27
Included in earnings	0		9
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		(31)
Settlements	0		0
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	5		5
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		2	[5]
Trading Account Assets [Member] | Equity Securities
Beginning balance			123
Included in earnings			13
OCI			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases			0
Sales			0
Settlements			(136)
Transfers to other balance sheet line items			0
Transfers into Level 3			0
Transfers out of Level 3			0
Fair value, ending balance			0
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period			0	[5]
Available-for-sale Securities [Member]
Beginning balance	1,041		1,136
Included in earnings	(7)	[1]	(7)	[8]
OCI	42		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	166		198
Sales	0		(4)
Settlements	(328)		(233)
Transfers to other balance sheet line items	0		49
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	914		1,041
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	(7)	[1],[6]	(6)	[5],[8]
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member]
Beginning balance	58		74
Included in earnings	0		1
OCI	0		(2)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		(4)
Settlements	(12)		(11)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	46		58
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		0
Available-for-sale Securities [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]
Beginning balance	221		347
Included in earnings	(7)		(8)
OCI	35		2
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(40)		(71)
Transfers to other balance sheet line items	0		49
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	209		221
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	(7)	[6]	(6)	[5]
Available-for-sale Securities [Member] | Asset-backed Securities [Member]
Beginning balance	16		20
Included in earnings	0		0
OCI	7		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(2)		(4)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	21		16
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		0
Available-for-sale Securities [Member] | Corporate And Other Debt Securities [Member]
Beginning balance	5		5
Included in earnings	0		0
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	2		0
Sales	0		0
Settlements	(2)		0
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	5		5
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		0
Available-for-sale Securities [Member] | Equity Securities, Other [Member]
Beginning balance	741		690
Included in earnings	0		0
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	164		198
Sales	0		0
Settlements	(272)		(147)
Transfers to other balance sheet line items	0		0
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	633		741
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	0		0
Loans Held-for-Sale | Corporate and Other Loans
Beginning balance			5
Included in earnings			(1)	[9]
OCI			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases			0
Sales			0
Settlements			(4)
Transfers to other balance sheet line items			0
Transfers into Level 3			0
Transfers out of Level 3			0
Fair value, ending balance			0
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period			0
Loans Held-for-Sale | Residential Mortgage, Loans Held For Sale [Member]
Beginning balance	1		2
Included in earnings	0		(1)	[10]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	(11)		(18)
Settlements	0		(1)
Transfers to other balance sheet line items	4		1
Transfers into Level 3	22		23
Transfers out of Level 3	(8)		(3)
Fair value, ending balance	8		1
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	(1)		0
Loans Held For Investment [Member]
Beginning balance	433		492
Included in earnings	7	[11]	14	[11]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0		0
Sales	0		0
Settlements	(49)		(59)
Transfers to other balance sheet line items	(15)		13
Transfers into Level 3	4		0
Transfers out of Level 3	(1)		(1)
Fair value, ending balance	379		433
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	11	[11],[6]	(1)	[11],[5]
Other Assets And Liabilities, Net [Member]
Beginning balance	62		(24)
Included in earnings	926	[10]	349	[10]
OCI	0		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	(31)		0
Sales	0		0
Settlements	26		8
Transfers to other balance sheet line items	(882)		271
Transfers into Level 3	0		0
Transfers out of Level 3	0		0
Fair value, ending balance	101		62
Change in unrealized gains / (losses) included in earnings for the period related to financial assets still held at the end of period	$ 0		$ 0

[1] Amounts included in earnings are generally recorded in net securities gains; however, any related hedge ineffectiveness is recorded in trading income.

[2] Amounts included in earnings are recorded in trading income.

[3] Amount recorded in OCI was the effective portion of the cash flow hedges related to the Company’s probable forecasted sale of its shares of Coke common stock. The Company ceased hedge accounting and terminated the forward contracts on the Coke Common stock during the third quarter of 2012, as discussed in Note 16, “Derivative Financial Instruments.”

[4] Amount recorded in OCI is the effective portion of the cash flow hedges related to the Company’s probable forecasted sale of its shares of Coke common stock as discussed in Note 16, “Derivative Financial Instruments.”

[5] Change in unrealized gains/(losses) included in earnings for the period related to financial assets still held at December 31, 2011.

[6] Change in unrealized gains/(losses) included in earnings during the period related to financial assets still held at December 31, 2012.

[7] Amounts included in earnings do not include losses accrued as a result of the ARS settlements discussed in Note 19, "Contingencies."

[8] Amounts included in earnings are recorded in net securities gains.

[9] Amounts included in earnings are recorded in other noninterest income.

[10] Amounts included in earnings are net of issuances, fair value changes, and expirations and are recorded in mortgage production related income/(loss).

[11] Amounts are generally included in mortgage production related income/(loss); however, the mark on certain fair value loans is included in trading income.