Summary of Significant Accounting and Reporting Policies - ALLL (Details) $ in Millions	Dec. 31, 2020 USD ($)
Large Commercial Loans and Leases
Financing Receivable, Recorded Investment, Past Due
Larger commercial loans, subject to impairment review	$ 1

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.

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