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Loans - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Accrued interest receivable	$ 1,400
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	337	$ 178
Loans held for sale	1,056	400
Performing
Loans and Leases Receivable Disclosure [Line Items]
Troubled debt restructurings included in impaired loans	1,700	1,700
Federal Home Loan banks
Loans and Leases Receivable Disclosure [Line Items]
Loans Pledged as Collateral	15,500	14,600
Line of Credit Facility, Remaining Borrowing Capacity	18,900	18,700
Federal Reserve Discount Window
Loans and Leases Receivable Disclosure [Line Items]
Loans Pledged as Collateral	6,200	6,700
Line of Credit Facility, Remaining Borrowing Capacity	4,900	5,300
Consumer Banking | Performing
Loans and Leases Receivable Disclosure [Line Items]
Troubled debt restructurings included in impaired loans	1,200	1,100
Commercial Banking | Performing
Loans and Leases Receivable Disclosure [Line Items]
Troubled debt restructurings included in impaired loans	249	$ 224
Domestic credit card: | Credit Card
Loans and Leases Receivable Disclosure [Line Items]
Financing Receivable, Past Due, Revolving, Converted To Term Loan	$ 160

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- Definition

Financing Receivable, Before Allowance For Credit Loss, Accrued Interest Receivable

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

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-Publisher FASB
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-Topic 310
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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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