Fair Value Accounting and Measurement - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016
Financial assets
Investment securities available for sale	$ 228,593	$ 267,857
Investment securities held to maturity	52,621	58,928
Accrued interest receivable	3,020	2,802
Mortgage servicing rights, net	1,600	1,700
Financial liabilities
Accrued interest payable	208	189
Carrying Amount
Financial assets
Cash and cash equivalents	24,292	22,650
Investment securities available for sale	228,593	267,857
Investment securities held to maturity	51,872	56,038
Loans held for sale		917
Loans receivable, net	726,786	619,844
FHLB stock	4,368	4,403
Accrued interest receivable	3,020	2,802
Mortgage servicing rights, net	986	998
Financial liabilities
Borrowings	77,427	80,672
Accrued interest payable	208	189
Carrying Amount \| Demand deposits
Financial liabilities
Deposits	612,286	564,174
Carrying Amount \| Time deposits
Financial liabilities
Deposits	211,474	159,113
Estimated Fair Value
Financial assets
Cash and cash equivalents	24,292	22,650
Investment securities available for sale	228,593	267,857
Investment securities held to maturity	52,621	58,928
Loans held for sale		917
Loans receivable, net	723,848	631,754
FHLB stock	4,368	4,403
Accrued interest receivable	3,020	2,802
Mortgage servicing rights, net	1,600	1,703
Financial liabilities
Borrowings	80,338	85,867
Accrued interest payable	208	189
Estimated Fair Value \| Demand deposits
Financial liabilities
Deposits	612,286	564,174
Estimated Fair Value \| Time deposits
Financial liabilities
Deposits	211,072	160,354
Estimated Fair Value \| Level 1
Financial assets
Cash and cash equivalents	24,292	22,650
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Loans held for sale		0
Loans receivable, net	0	0
FHLB stock	0	0
Accrued interest receivable	0	0
Mortgage servicing rights, net	0	0
Financial liabilities
Borrowings	0	0
Accrued interest payable	0	0
Estimated Fair Value \| Level 1 \| Demand deposits
Financial liabilities
Deposits	612,286	564,174
Estimated Fair Value \| Level 1 \| Time deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 2
Financial assets
Cash and cash equivalents	0	0
Investment securities available for sale	228,593	267,857
Investment securities held to maturity	52,621	58,928
Loans held for sale		917
Loans receivable, net	0	0
FHLB stock	4,368	4,403
Accrued interest receivable	3,020	2,802
Mortgage servicing rights, net	0	0
Financial liabilities
Borrowings	80,338	85,867
Accrued interest payable	208	189
Estimated Fair Value \| Level 2 \| Demand deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 2 \| Time deposits
Financial liabilities
Deposits	211,072	160,354
Estimated Fair Value \| Level 3
Financial assets
Cash and cash equivalents	0	0
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Loans held for sale		0
Loans receivable, net	723,848	631,754
FHLB stock	0	0
Accrued interest receivable	0	0
Mortgage servicing rights, net	1,600	1,703
Financial liabilities
Borrowings	0	0
Accrued interest payable	0	0
Estimated Fair Value \| Level 3 \| Demand deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 3 \| Time deposits
Financial liabilities
Deposits	$ 0	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investments in debt securities classified as held-to-maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of interest payable on debt, including, but not limited to, trade payables.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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