Investment Securities - Textuals (Details) - USD ($)	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Summary of Investment Holdings [Line Items]
Securities classified as trading	$ 0		$ 0
Debt Securities, Held-to-maturity	0		0
Allowance for credit losses on loans	70,185,000	$ 37,993,000	36,171,000
Accrued Investment Income Receivable	3,600,000		3,700,000
Available-for-sale Securities [Member]
Summary of Investment Holdings [Line Items]
Allowance for credit losses on loans	$ 0		$ 0

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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