Credit Arrangements	9 Months Ended
	Mar. 31, 2023
Credit Arrangements [Abstract]
Credit Arrangements	6.  CREDIT ARRANGEMENTS On August 28, 2020, the Company entered a two-year secured $25.0 million revolving line of credit with Dubuque Bank and Trust Company, with an interest rate of 1.50% plus LIBOR, subject to a floor of 3.00%. The revolving line of credit was secured by essentially all the Company’s assets, excluding real property, and required the Company to maintain compliance with certain financial and non-financial covenants. This line of credit was subsequently canceled in the first quarter of fiscal year 2022. On September 8, 2021, the Company, as the borrower, entered into a credit agreement (the “Credit Agreement”) with Wells Fargo Bank, National Association (the “Lender”), and the other lenders party thereto. The Credit Agreement has a five-year term and provides for up to an $85 million revolving line of credit. Subject to certain conditions, the Credit Agreement also provides for the issuance of letters of credit in an aggregate amount up to $5 million which, upon issuance, would be deemed advances under the revolving line of credit. The Company’s $1.1 million letters of credit previously issued by the Lender are being treated as outstanding under the Credit Agreement and reduce the amount of available borrowings under the revolving line of credit. Proceeds of borrowings were used to refinance all indebtedness owed to Dubuque Bank & Trust and for working capital purposes. The Company’s obligations under the Credit Agreement are secured by substantially all its assets, excluding real property. Subject to certain conditions, borrowings under the Credit Agreement bear interest at LIBOR plus 1.25% or 1.50% per annum, or an effective interest rate of 6.1% on March 31, 2023. When LIBOR becomes unavailable, the replacement rate will be determined pursuant to the terms of the Credit Agreement. The Credit Agreement contains customary representations, warranties, and covenants, including a financial covenant to maintain a fixed coverage ratio of not less than 1.00 to 1.00. In addition, the Loan Agreement places restrictions on the Company’s ability to incur additional indebtedness, to create liens or other encumbrances, to sell or otherwise dispose of assets, and to merge or consolidate with other entities. As of March 31, 2023, management believes the Company was in compliance with all covenants. On April 18, 2022, the Company, as the borrower, entered into a first amendment to the September 8, 2021, Credit Agreement (“First Amendment to the Credit Agreement”), with the Lender and the lenders thereto. The amendment to the Credit Agreement changed the definition of the term ‘Payment Conditions’ and further defines “default” or “event of default” and the calculation of the Fixed Charge Coverage Ratio. As of March 31, 2023, there was $17.7 million outstanding under the Credit Agreement, exclusive of fees and letters of credit. Letters of credit outstanding at the Lender as of March 31, 2023, totaled $1.1 million.