Off-balance Sheet Lending-related Financial Instruments, Guarantees, and Other Commitments - Other Unfunded Commitments and Standby Letters of Credit (Details) $ in Billions	Dec. 31, 2017 USD ($)
Maximum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Secured clearance advance facility outstanding commitment	$ 1.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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