Loans - Collateral-Dependent Loans (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Consumer Loans [Member] \| Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collateral-dependent loans	$ 805	$ 803
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collateral-dependent loans	$ 480	$ 227

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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