Loans and Leases - Quality of Non-Covered Loans (Excluding PCI Loans and Leases) (Parenthetical) (Detail) - Taxi Medallion Loans - Commercial and Industrial - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 0	$ 0
Loans 90 Days Or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 22,900,000	$ 30,400,000