Fair Value Measurements - Schedule of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Financial Assets | Cash and Cash Equivalents
Financial Instruments Owned Carrying Amount	$ 54,245	$ 35,400
Financial Assets | Investment in Federal Home Loan Bank Stock
Financial Instruments Owned Carrying Amount	6,390	5,233
Financial Assets | Loans Receivable
Financial Instruments Owned Carrying Amount	2,141,929	1,846,405
Financial Assets | Interest-bearing time deposits
Financial Instruments Owned Carrying Amount	974	969
Financial Assets | Stock in Federal Reserve Bank of St. Louis
Financial Instruments Owned Carrying Amount	4,363	4,350
Financial Assets | Accrued interest receivable
Financial Instruments Owned Carrying Amount	12,116	10,189
Financial Liabilities | Note payable
Financial Instruments Owned Carrying Amount		3,000
Financial Liabilities | Deposits
Financial Instruments Owned Carrying Amount	2,184,847	1,893,695
Financial Liabilities | Securities Sold under Agreements to Repurchase
Financial Instruments Owned Carrying Amount		4,376
Financial Liabilities | Federal Home Loan Bank Advances
Financial Instruments Owned Carrying Amount	70,024	44,908
Financial Liabilities | Subordinated Debt
Financial Instruments Owned Carrying Amount	15,142	15,043
Financial Liabilities | Accrued interest payable
Financial Instruments Owned Carrying Amount	1,646	2,099
Fair Value, Inputs, Level 1 | Financial Assets | Cash and Cash Equivalents
Financial Instruments Owned Carrying Amount	54,245	35,400
Fair Value, Inputs, Level 1 | Financial Liabilities | Deposits
Financial Instruments Owned Carrying Amount	1,508,740	1,214,606
Fair Value, Inputs, Level 2 | Financial Assets | Investment in Federal Home Loan Bank Stock
Financial Instruments Owned Carrying Amount	6,390	5,233
Fair Value, Inputs, Level 2 | Financial Assets | Interest-bearing time deposits
Financial Instruments Owned Carrying Amount	974	969
Fair Value, Inputs, Level 2 | Financial Assets | Stock in Federal Reserve Bank of St. Louis
Financial Instruments Owned Carrying Amount	4,363	4,350
Fair Value, Inputs, Level 2 | Financial Assets | Accrued interest receivable
Financial Instruments Owned Carrying Amount	12,116	10,189
Fair Value, Inputs, Level 2 | Financial Liabilities | Securities Sold under Agreements to Repurchase
Financial Instruments Owned Carrying Amount		4,376
Fair Value, Inputs, Level 2 | Financial Liabilities | Federal Home Loan Bank Advances
Financial Instruments Owned Carrying Amount	72,136	45,547
Fair Value, Inputs, Level 2 | Financial Liabilities | Accrued interest payable
Financial Instruments Owned Carrying Amount	1,646	2,099
Fair Value, Inputs, Level 3 | Financial Assets | Loans Receivable
Financial Instruments Owned Carrying Amount	2,143,823	1,823,040
Fair Value, Inputs, Level 3 | Financial Liabilities | Note payable
Financial Instruments Owned Carrying Amount		3,000
Fair Value, Inputs, Level 3 | Financial Liabilities | Deposits
Financial Instruments Owned Carrying Amount	676,816	678,301
Fair Value, Inputs, Level 3 | Financial Liabilities | Subordinated Debt
Financial Instruments Owned Carrying Amount	$ 11,511	$ 15,267