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Loans and Allowance for Credit Losses - Performing Loans Classified as Troubled Debt Restructuring Loans (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020 USD ($)	Dec. 31, 2019	Jun. 30, 2020 USD ($)
Consumer Loan
Number of modifications	0	0	0	0
Commercial Loan
Number of modifications	0	0	1	0
Construction Real Estate
Number of modifications	0	0	0	0
Residential real estate loans
Number of modifications	0	0	1	0
Commercial Real Estate
Number of modifications	0	0	2	0
Performing Loans
Number of modifications			18		20
Recorded Investment			$ 7,897
Recorded Investment					$ 8,580
Performing Loans | Commercial Loan
Number of modifications			8		7
Recorded Investment			$ 2,976
Recorded Investment					$ 3,245
Performing Loans | Residential real estate loans
Number of modifications			3		3
Recorded Investment			$ 1,014
Recorded Investment					$ 791
Performing Loans | Commercial Real Estate
Number of modifications			7		10
Recorded Investment			$ 3,907
Recorded Investment					$ 4,544
Total Loans
Number of modifications	0	0	4	0

X

- Definition

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

+ References

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=121611835&loc=SL6953676-111524

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

+ References

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=121611835&loc=SL6953676-111524

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Amount of financing receivable modified as troubled debt restructuring.

+ References

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=121611835&loc=SL6953676-111524

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-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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