Loans and Allowance for Loan Losses - Troubled Debt Restructurings That Are Not Performing (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Number of contracts	3	2	3
Number of contracts	0	0	0
Nonperforming Financial Instruments [Member]
Number of contracts		12
Recorded investment, subsequent default	$ 0	$ 2,201
One-To-Four Family - Mixed Used Property [Member]
Number of contracts		1
Taxi Medallion Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Number of contracts		11
Recorded investment, subsequent default		$ 1,922
Commercial Business and Other Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Number of contracts		1
Recorded investment, subsequent default		$ 279

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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