Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Borrowings - Additional Information (Detail) - USD ($)	3 Months Ended
Borrowings - Additional Information (Detail) - USD ($)	Mar. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Securities sold under agreements to repurchase		$ 57,900,000	$ 43,700,000
Advances from the FHLB		135,100,000	165,800,000
Repayments of debt	$ 10,000,000.0
Securities Sold under Agreements to Repurchase
Debt Instrument [Line Items]
Pledged securities		72,900,000
Line of Credit
Debt Instrument [Line Items]
Overnight federal funds borrowed		0	85,000,000.0
Federal Home Loan Bank of New York \| Line of Credit
Debt Instrument [Line Items]
Overnight borrowings		$ 40,000,000.0	$ 200,000,000.0
Collateralized FHLB Advances
Debt Instrument [Line Items]
Long term debt prepayment fee	$ 356,000