Loan Portfolio and Allowance for Credit Losses, Recorded Investment in Loans by Loan Class (Details) - USD ($) $ in Thousands		Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable [Abstract]
Total loans		$ 4,540,559
Less: Allowance for credit losses on loans		45,285		$ 44,267	$ 50,155		$ 49,595
Net loans		4,495,274
Total loans, net				4,438,779
Less: Allowance for credit losses on loans			$ 46,178	44,267	50,155	$ 49,991
Net loans				4,394,512
New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans	[1]	3,152,645
Total loans, net	[1]			3,132,378
Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		1,387,914
Total loans, net				1,306,401
Real Estate Construction Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans		30,400		37,300
Residential Borrowers [Member]
Loans and Leases Receivable [Abstract]
Total loans		10,700		17,900
Commercial Borrowers Residential Purpose [Member]
Loans and Leases Receivable [Abstract]
Total loans		19,700		19,400
Commercial [Member]
Loans and Leases Receivable [Abstract]
Total loans		199,886
Less: Allowance for credit losses on loans		2,274		3,135	4,106		4,140
Total loans, net				200,200
Less: Allowance for credit losses on loans			2,177	3,135	4,106	4,052
Commercial [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans, net				177,952
Commercial [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans, net				22,248
Commercial [Member] | Commercial Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans		179,624
Total loans, net				168,716
Commercial [Member] | Commercial Real Estate [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans	[1]	151,978
Total loans, net	[1]			147,063
Commercial [Member] | Commercial Real Estate [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		27,646
Total loans, net				21,653
Commercial [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans		20,262
Total loans, net				31,484
Commercial [Member] | Other [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans	[1]	19,134
Total loans, net	[1]			30,889
Commercial [Member] | Other [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		1,128
Total loans, net				595
Commercial [Member] | PPP Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans		1,500		10,000
Real Estate Mortgage - 1 to 4 Family [Member]
Loans and Leases Receivable [Abstract]
Total loans		4,330,415
Less: Allowance for credit losses on loans		42,880		40,689	45,617		44,950
Total loans, net				4,229,163
Less: Allowance for credit losses on loans			43,931	40,689	45,617	45,507
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Loans and Leases Receivable [Abstract]
Total loans		4,018,378
Total loans, net				3,936,302
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans	[1]	2,747,210
Total loans, net	[1]			2,723,734
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		1,271,168
Total loans, net				1,212,568
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans		58,279
Total loans, net				61,885
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	[1]	45,428
Total loans, net	[1]			48,190
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		12,851
Total loans, net				13,695
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Loans and Leases Receivable [Abstract]
Total loans		253,758
Total loans, net				230,976
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	[1]	180,720
Total loans, net	[1]			175,134
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		73,038
Total loans, net				55,842
Installment [Member]
Loans and Leases Receivable [Abstract]
Total loans		10,258
Less: Allowance for credit losses on loans		131		443	432		$ 505
Total loans, net				9,416
Less: Allowance for credit losses on loans			$ 70	443	$ 432	$ 432
Installment [Member] | New York and Other States [Member]
Loans and Leases Receivable [Abstract]
Total loans	[1]	8,175
Total loans, net	[1]			7,368
Installment [Member] | Florida [Member]
Loans and Leases Receivable [Abstract]
Total loans		$ 2,083
Total loans, net				$ 2,048

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