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Loans and Allowance for Credit Losses - Classes of loans information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($)	Jun. 30, 2020 USD ($)
Provision for credit losses | $	$ 612	$ 388	$ 1,385	$ 1,284
ACL | $	$ 35,471		$ 35,471		$ 25,139
Consumer Loan
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 Loan
Amortization period of loans			5 years
Amortization period for commercial operating lines of credit or agricultural production lines			1 year
Construction Real Estate | Minimum
Maturities of single-family residential construction loans			6 months
Maturities of multifamily or commercial construction loans			12 months
Construction Real Estate | Maximum
Maturities of single-family residential construction loans			12 months
Maturities of multifamily or commercial construction loans			24 months
Residential real estate loans
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 loans | Minimum
Number of family residences | item			1
Residential real estate loans | Maximum
Number of family residences | item			4
Residential real estate loans | Construction Real Estate
Amortization period of loans			30 years
Residential real estate loans | Single Family [Member]
Maximum percentage of appraised value or purchase price that loans cannot exceed			90.00%
Residential real estate loans | Multifamily [Member]
Maximum percentage of appraised value or purchase price that loans cannot exceed			85.00%
Amortization period of loans			25 years
Commercial Real Estate
Maximum percentage of appraised value or purchase price that loans cannot exceed			80.00%
Amortization period of loans			25 years
Term of fixed interest applicabality 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
Commercial Real Estate | Construction Real Estate
Amortization period of loans			25 years

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Amortization term of agriculture loans if 80% of loan-to-value ratio.

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Maturities of construction loans related to multi family and commercial residential real estate.

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

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

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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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