Loans and Allowance for Loan Losses - Loans Modified and Classified as TDR (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number	2	3	1
Balance	$ 7,853	$ 951	$ 1,620
Principal amount forgiven	$ 0
Empire
Number \| loan	7
Balance	$ 3,500
One-To-Four Family - Mixed Used Property [Member]
Number	1
Balance	$ 270
Commercial Real Estate
Number	1
Balance	$ 7,583
Commercial Business and Other [Member] \| Extended Maturity [Member]
Number		3	1
Balance		$ 951	$ 1,620

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=118936363&loc=SL6953676-111524

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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