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Loans and Allowance for Credit Losses - Classes of loans information (Details) $ in Thousands	3 Months Ended
	Sep. 30, 2021 USD ($) item	Sep. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)
Provision for credit losses	$ (305)	$ 1,000
ACL	$ 32,543		$ 33,222
Consumer loans
Amortization period of loans	5 years
Consumer Loans, Home Equity Lines Of Credit
Maximum percentage of appraised value or purchase price that loans cannot exceed	100.00%
Amortization period of loans	10 years
Consumer Loans, Other Than Home Equity Lines Of Credit
Maximum percentage of appraised value or purchase price that loans cannot exceed	100.00%
Amortization period of loans	60 months
Commercial loans
Amortization period of loans	5 years
Amortization period of multi-family residential loans if balloon maturities	1 year
Residential Real Estate
Fixed-rate and adjustable-rate mortgage (ARM) loans amortization period (in years)	30 years
Amortization period of multi-family residential loans if balloon maturities	10 years
Residential Real Estate | Minimum
Number of family residences | item	1
Residential Real Estate | Maximum
Number of family residences | item	4
Residential Real Estate | Single Family
Maximum percentage of appraised value or purchase price that loans cannot exceed	90.00%
Residential Real Estate | Multifamily
Maximum percentage of appraised value or purchase price that loans cannot exceed	85.00%
Amortization period of loans	25 years
Commercial
Amortization period of loans	25 years
Term of fixed interest applicability on loans	10 years
Term of variable interest applicability on loans	7 years
Agricultural real estate terms if 80% loan-to-value ratio	25 years
Agricultural real estate terms if 75% loan-to-value ratio	30 years
Residential Real Estate
Amortization period of loans	30 years
Residential Real Estate | Minimum
Maturities of single-family residential construction loans	6 months
Residential Real Estate | Maximum
Maturities of single-family residential construction loans	12 months
Commercial Real Estate
Amortization period of loans	25 years
Construction Real Estate
Average term of construction loans	9 months
Construction Real Estate | Minimum
Maturities of multifamily or commercial construction loans	12 months
Construction Real Estate | Maximum
Maturities of multifamily or commercial construction loans	24 months
Modifications for the purpose of extending the maturity date | Construction Real Estate
Incremental period that the loan maturity can be extended to	3 months
Number of construction loans outstanding, for which a modification had been agreed to	43		48
Construction loans outstanding, for which a modification had been agreed to	$ 29,000		$ 28,500

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Amortization term of fixed-rate and adjustable rate mortgage loans.

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Term of adjusted interest rate applicability on loans.

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Amortization term of loans.

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Percentage of appraised value or purchase price that loans cannot exceed.

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Term of fixed interest rate applicability on loans

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Represents the number of family residences.

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Represents the pure numeric value of Number of Loans Modified for Other Than TDR, as of the indicated date.

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Amortization term of multi family residences loans if the balloon maturities.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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