Loans and Allowance for Loan Losses - Activity in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Beginning balance	$ 28,098	$ 21,015	$ 21,751	$ 20,945
Impact of CECL Adoption			379
Charge-off's	(1,030)	(1,114)	(2,289)	(2,252)
Recoveries	23	135	133	371
Provision (benefit)	9,619	1,474	16,736	2,446
Ending balance	36,710	21,510	36,710	21,510
Multi-family Residential Portfolio Segment [Member]
Beginning balance	5,895	5,493	5,391	5,676
Impact of CECL Adoption			(650)
Charge-off's		(1)		(1)
Recoveries	7	11	13	24
Provision (benefit)	3,033	3	4,181	(193)
Ending balance	8,935	5,506	8,935	5,506
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	6,791	4,278	4,429	4,315
Impact of CECL Adoption			1,170
Recoveries		7		7
Provision (benefit)	180	(20)	1,372	(57)
Ending balance	6,971	4,265	6,971	4,265
One-To-Four Family - Mixed-Use Property Portfolio Segment [Member]
Beginning balance	2,170	1,791	1,817	1,867
Impact of CECL Adoption			(55)
Charge-off's	(3)		(3)	(1)
Recoveries		2	78	88
Provision (benefit)	659	(7)	989	(168)
Ending balance	2,826	1,786	2,826	1,786
One-To-Four Family - Residential Portfolio Segment [Member]
Beginning balance	892	731	756	749
Impact of CECL Adoption			(160)
Charge-off's		(113)		(113)
Recoveries	3	3	8	7
Provision (benefit)	266	125	557	103
Ending balance	1,161	746	1,161	746
Construction Portfolio Segment [Member]
Beginning balance	185	351	441	329
Impact of CECL Adoption			(279)
Provision (benefit)	(2)	30	21	52
Ending balance	183	381	183	381
Small Business Administration Portfolio Segment [Member]
Beginning balance	1,528	409	363	418
Impact of CECL Adoption			1,180
Charge-off's	(178)		(178)
Recoveries	13	16	20	20
Provision (benefit)	23	(43)	1	(56)
Ending balance	1,386	382	1,386	382
Taxi Medallion Portfolio Segment [Member]
Recoveries		50		134
Provision (benefit)		(50)		(134)
Commercial Business and Other Portfolio Segment [Member]
Beginning balance	10,637	7,962	8,554	7,591
Impact of CECL Adoption			(827)
Charge-off's	(849)	(1,000)	(2,108)	(2,137)
Recoveries		46	14	91
Provision (benefit)	5,460	1,436	9,615	2,899
Ending balance	$ 15,248	$ 8,444	$ 15,248	$ 8,444

Amount of impact on allowance for credit loss on financing receivable due to adoption of new accounting standard.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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