Fair Value of Financial Instruments - Carrying value and fair value of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Financial assets:
Loans receivable, net	$ 457,178	$ 461,196
Held to maturity securities, Amortized cost	104,227
Financial liabilities:
Certificates of deposit	135,840	160,303
Advances from Federal Home Loan Bank	20,000	41,000
Level 2
Financial assets:
Held to maturity securities, Amortized cost	95,102
Level 3
Financial assets:
Loans receivable, net	460,400	472,292
Financial liabilities:
Certificates of deposit	136,909	161,057
Advances from Federal Home Loan Bank	20,260	42,098
Carrying Value
Financial assets:
Loans receivable, net	457,178	461,196
Held to maturity securities, Amortized cost	104,227
Financial liabilities:
Certificates of deposit	135,840	160,303
Advances from Federal Home Loan Bank	20,000	41,000
Fair Value
Financial assets:
Loans receivable, net	460,400	472,292
Held to maturity securities, Amortized cost	95,102
Financial liabilities:
Certificates of deposit	136,909	161,057
Advances from Federal Home Loan Bank	$ 20,260	$ 42,098

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The aggregate amount of certificate of deposit liabilities.

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