Loans and Allowance for Credit Losses - Performing Loans Classified as Troubled Debt Restructuring Loans (Details)	12 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($)
Number of modifications \| loan	3
Recorded Investment	$ 894,000
Performing Loans
Number of modifications	12,000	20,000
Recorded Investment	$ 3,241,000
Recorded Investment		$ 8,580,000
Performing Loans \| Commercial loans
Number of modifications	7,000	7,000
Recorded Investment	$ 1,397,000
Recorded Investment		$ 3,245,000
Performing Loans \| Residential Real Estate
Number of modifications	1,000	3,000
Recorded Investment	$ 895,000
Recorded Investment		$ 791,000
Performing Loans \| Commercial
Number of modifications	4,000	10,000
Recorded Investment	$ 949,000
Recorded Investment		$ 4,544,000

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

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

+ References

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- Definition

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

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