Amount, before allowance for credit loss, of financing receivable.

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Loans and Leases - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Loans and Leases - Narrative (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest receivable	$ 91,600,000		$ 91,600,000			$ 106,500,000
Jumbo residential mortgage loans	34,343,691,000		34,343,691,000			$ 34,497,464,000
Impairment charges	$ 0	$ 22,000	$ 224,000	$ 43,000
Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Jumbo residential mortgage loans					$ 423,000,000.0