Fair Value of Financial Instruments - Summary of Carrying Amounts and Estimated Fair Values of Bank's Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019
Financial assets:
Investment securities held to maturity	$ 267,704	$ 346,243
Investment securities available for sale	45,992	72,228
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	84,912	60,029
Investment securities held to maturity	263,626	345,545
Investment securities available for sale	45,992	72,228
Loans receivable, net	1,220,682	1,093,121
Accrued interest receivable	5,384	4,797
FHLB stock	6,026	6,255
Financial liabilities:
Mortgage escrow funds	7,924	9,355
Accrued interest payable	256	209
FHLB advances	106,121	111,216
Carrying Amount [Member] \| Derivatives – Interest Rate Contracts [Member]
Financial assets:
Derivative assets - interest rate contracts	6,644	1,339
Financial liabilities:
Derivative liabilities - interest rate contracts	6,644	1,339
Carrying Amount [Member] \| Demand, NOW, Money Market Deposits and Savings Accounts [Member]
Financial liabilities:
Time deposits	797,036	770,426
Carrying Amount [Member] \| Time Deposits [Member]
Financial liabilities:
Time deposits	482,550	455,395
Total [Member]
Financial assets:
Cash and cash equivalents	84,912	60,029
Investment securities held to maturity	267,704	346,243
Investment securities available for sale	45,992	72,228
Loans receivable, net	1,181,218	1,092,878
Accrued interest receivable	5,384	4,797
Financial liabilities:
Mortgage escrow funds	7,924	9,355
Accrued interest payable	256	209
FHLB advances	110,336	111,818
Total [Member] \| Derivatives – Interest Rate Contracts [Member]
Financial assets:
Derivative assets - interest rate contracts	6,644	1,339
Financial liabilities:
Derivative liabilities - interest rate contracts	6,644	1,339
Total [Member] \| Demand, NOW, Money Market Deposits and Savings Accounts [Member]
Financial liabilities:
Time deposits	797,036	770,426
Total [Member] \| Time Deposits [Member]
Financial liabilities:
Time deposits	491,942	460,554
Level 1 [Member]
Financial assets:
Cash and cash equivalents	84,912	60,029
Financial liabilities:
Mortgage escrow funds	7,924	9,355
Accrued interest payable	1	16
Level 1 [Member] \| Demand, NOW, Money Market Deposits and Savings Accounts [Member]
Financial liabilities:
Time deposits	797,036	770,426
Level 2 [Member]
Financial assets:
Investment securities held to maturity	262,804	346,243
Investment securities available for sale	45,992	72,228
Accrued interest receivable	1,142	1,330
Financial liabilities:
Accrued interest payable	255	193
FHLB advances	110,336	111,818
Level 2 [Member] \| Derivatives – Interest Rate Contracts [Member]
Financial assets:
Derivative assets - interest rate contracts	6,644	1,339
Financial liabilities:
Derivative liabilities - interest rate contracts	6,644	1,339
Level 2 [Member] \| Time Deposits [Member]
Financial liabilities:
Time deposits	491,942	460,554
Level 3 [Member]
Financial assets:
Investment securities held to maturity	4,900
Loans receivable, net	1,181,218	1,092,878
Accrued interest receivable	$ 4,242	$ 3,467

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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

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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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