Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Selected Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities held-to-maturity, amortized cost	$ 74,217	$ 57,868
Securities available for sale, fair value	839,869	777,236
Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	14,631	10,683
Interest rate swaps	11,585	3,544
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,890	7,894
Securities available for sale, fair value	553,828	572,184
Other Debt Obligations [Member]
Securities held-to-maturity, amortized cost	66,327	49,974
Securities available for sale, fair value	286,041	205,052
Reported Value Measurement [Member]
Cash and due from banks	186,407	81,723
Loans	6,607,264	6,638,105
FHLB-NY stock	33,891	35,937
Accrued interest receivable	37,308	38,698
Deposits	6,452,895	6,385,445
Borrowings	877,122	815,544
Accrued interest payable	5,740	4,777
Reported Value Measurement [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	35,636	10,683
Interest rate swaps	11,585	25,071
Reported Value Measurement [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,890	7,894
Securities available for sale, fair value	553,828	572,184
Reported Value Measurement [Member] \| Other Debt Obligations [Member]
Securities held-to-maturity, amortized cost	67,313	49,974
Securities available for sale, fair value	286,041	205,052
Estimate of Fair Value Measurement [Member]
Cash and due from banks	186,407	81,723
Loans	6,610,591	6,687,125
FHLB-NY stock	33,891	35,937
Accrued interest receivable	37,308	38,698
Deposits	6,444,392	6,385,276
Borrowings	868,589	816,012
Accrued interest payable	5,740	4,777
Estimate of Fair Value Measurement [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	35,636	10,683
Interest rate swaps	11,585	25,071
Estimate of Fair Value Measurement [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,880	8,667
Securities available for sale, fair value	553,828	572,184
Estimate of Fair Value Measurement [Member] \| Other Debt Obligations [Member]
Securities held-to-maturity, amortized cost	61,839	53,362
Securities available for sale, fair value	286,041	205,052
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	186,407	81,723
Accrued interest receivable	8
Deposits	5,566,578	5,438,870
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Other Debt Obligations [Member]
Securities available for sale, fair value	11,937	12,485
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
FHLB-NY stock	33,891	35,937
Accrued interest receivable	1,760	1,574
Deposits	877,814	946,406
Borrowings	810,634	759,540
Accrued interest payable	5,740	4,777
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	35,636	10,683
Interest rate swaps	11,585	25,071
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,880	8,667
Securities available for sale, fair value	553,828	572,184
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Other Debt Obligations [Member]
Securities available for sale, fair value	272,364	190,872
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans	6,610,591	6,687,125
Accrued interest receivable	35,540	37,124
Borrowings	57,955	56,472
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Debt Obligations [Member]
Securities held-to-maturity, amortized cost	61,839	53,362
Securities available for sale, fair value	$ 1,740	$ 1,695

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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