Loan Portfolio and Allowance for Credit Losses, Recorded Investment in Loans by Loan Class (Details) - USD ($) $ in Thousands		Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Loans and Leases Receivable [Abstract]
Total loans, net		$ 5,070,856		$ 5,002,879
Less: Allowance for credit losses		49,950	$ 49,772	48,578	$ 47,226	$ 46,914	$ 46,032
Net loans		5,020,906		4,954,301
New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	3,271,994		3,259,038
Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		1,798,862		1,743,841
Real Estate Construction Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		24,700		29,100
Residential Borrowers [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		7,900		8,000
Commercial Borrowers Residential Purpose [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		16,800		21,100
Commercial [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		280,261		273,515
Less: Allowance for credit losses		3,352	3,429	2,735	2,713	2,610	2,596
Commercial [Member] | Commercial Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		259,563		252,255
Commercial [Member] | Commercial Real Estate [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	220,645		212,754
Commercial [Member] | Commercial Real Estate [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		38,918		39,501
Commercial [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		20,698		21,260
Commercial [Member] | Other [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	19,934		20,863
Commercial [Member] | Other [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		764		397
Commercial [Member] | PPP Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		292		620
Real Estate Mortgage - 1 to 4 Family [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		4,776,092		4,712,478
Less: Allowance for credit losses		46,392	46,129	45,625	44,285	44,067	43,271
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		4,325,864		4,307,105
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	2,746,180		2,756,914
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		1,579,684		1,550,191
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		56,810		57,958
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	43,501		44,152
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		13,309		13,806
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		393,418		347,415
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	231,275		212,298
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		162,143		135,117
Installment [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		14,503		16,886
Less: Allowance for credit losses		206	$ 214	218	$ 228	$ 237	$ 165
Installment [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net	[1]	10,459		12,057
Installment [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net		$ 4,044		$ 4,829

[1] Includes New York, New Jersey, Vermont and Massachusetts.