ALLL Impact for NPL Loans Transferred to Loans Held for Sale

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Allowance for commercial unfunded loan commitments and letters of credit

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Percentage of Carrying Value

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Carring Amount of Loans Held For Investment Sold

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Unfunded Commercial Loan Commitments and Letters of Credit

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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This item represents the estimated amount of gains and losses from fair value changes included in earnings that are attributable to changes in the instrument-specific credit risk of liabilities with fair values that have been significantly affected during the reporting period by changes in the instrument-specific credit risk.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair Value Measurement and Election - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
ALLL Impact for NPL Loans Transferred to Loans Held for Sale	$ 11
Estimated Fair Value of Loan Portfolio's Net Carrying Value, Percentage	100.00%			100.00%		100.00%
Assets	$ 187,036			$ 187,036		$ 190,328
Loans Receivable, Fair Value Disclosure	262			262		272
Allowance for Loan and Lease Losses, Write-offs	102	$ 164		356	$ 473
Loans held for investment sold	178	2,300		1,994	2,954
Gain (Loss) on Sales of Loans, Net	9	40		22	71
Unfunded loan commitments and letters of credit	63,900			63,900		56,500
Allowance for unfunded loan commitments and letters of credit	64			64		59
Total Return Swap \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	2,400			2,400		2,300
Interest Rate Lock Commitments [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	41	64		138	181
Trading Account Assets [Member] \| Commercial and Corporate Leveraged Loans [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	261			261		284
Long-term Debt [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Option, Credit Risk, Gains (Losses) on Liabilities		$ 2			$ 24
Loans Held For Sale [Member]
Loans Receivable, Fair Value Disclosure	1,883			1,883		1,891
Commercial and Corporate Loans [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Assets	584			584		704
Commercial and Corporate Loans [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member] \| Preference Shares [Member]
Assets	2			2		3
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	0			0		0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans Receivable, Fair Value Disclosure	262			262		272
Other Real Estate Owned [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Asset Impairment Charges	2			3		6
Other Assets [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Asset Impairment Charges	1			7		64
Other Assets [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Land [Member]
Asset Impairment Charges	1			1		5
Other Assets [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Property Subject to Operating Lease [Member]
Asset Impairment Charges						59
Affordable Housing [Member]
Asset Impairment Charges						15
Gains (Losses) on Sales of Investment Real Estate	$ 0			19
Affordable Housing [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Asset Impairment Charges			$ 36	$ 0		$ 21