Loans and Allowance for Loan Losses - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loans	$ 6,633,866	$ 6,701,629
Net unamortized premiums and unearned loan fees	4,239	3,045
Aggregate outstanding loans	6,638,105	6,704,674
Multi-Family Residential [Member]
Loans	2,517,026	2,533,952
Commercial Real Estate Loans [Member]
Loans	1,775,629	1,754,754
One-To-Four Family - Mixed Used Property [Member]
Loans	571,795	602,981
One-To-Four Family - Residential [Member]
Loans	268,255	245,211
Co-Operative Apartments [Member]
Loans	8,316	8,051
Construction Portfolio Segment [Member]
Loans	59,761	83,322
Aggregate outstanding loans	59,473	83,161
Small Business Administration [Member]
Loans	93,811	167,376
Small Business Administration [Member] \| Small Business Administration, Cares Act, Paycheck Protection Program
Loans	77,400	151,900
Taxi Medallion [Member]
Loans		2,757
Commercial Business and Other [Member]
Loans	$ 1,339,273	$ 1,303,225

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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