Loans and Leases - Quality of Loans Held for Investment (Parenthetical) (Details) - Taxi Medallion Loans - Commercial and Industrial - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Loans 90 Days Or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	$ 7	$ 19
Financing Receivable, 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	$ 0	$ 0

Amount of financing receivable past due.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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