Borrowings - Additional Information (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Federal Home Loan Bank borrowings	$ 9,000,000	$ 44,200,000
Pledged Assets Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment	0	7,100,000
U.S. Bank
Debt Instrument [Line Items]
Maximum line of credit borrowing in master contract agreement	$ 5,000,000	$ 5,000,000
Interest rate	0.75%	0.75%
Line of credit outstanding	$ 0	$ 0
Pledged Assets Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment		7,100,000
Federal Home Loan Bank ("FHLB")
Debt Instrument [Line Items]
Maximum line of credit borrowing in master contract agreement	130,801,182
Line of credit outstanding	0	0
Federal Home Loan Bank borrowings	9,000,000	44,200,000
Collateralized Agreements	$ 170,769,631	$ 153,925,211

The total of collateralized agreements including securities purchased under agreements to resell (repos), borrowed securities, and secured demand notes.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fair value, as of the date of each statement of financial position presented, of other securities, classified as available for sale or held for investment, which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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