Cover [Abstract] Document Type Entity Central Index Key Document Period End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Quarterly Report Document Transition Report Document Fiscal Period Focus Amendment Flag Entity File Number Entity Registrant Name Entity Incorportion, State or Country Code Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line Two Entity Address, City or Town Entity Address, State or Province Entity Address, Postal Zip Code City Area Code Local Phone Number Title of 12(b) Security Trading Symbol Entity Current Reporting Status Entity Interactive Data Current Entity Filer Category Entity Small Business Entity Emerging Growth Company Entity Shell Company Entity Common Stock, Shares Outstanding Statement of Financial Position [Abstract] ASSETS: Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Investment securities Fair Value Fair Value Trade accounts receivable, net of allowance of $3,000 Income tax receivable Inventories: Raw materials Work-in-process Costs related to contracts in process Total inventories Inventory, Net Prepaid expenses and other current assets Total current assets Assets, Current Property, plant and equipment, net Total assets Assets LIABILITIES AND STOCKHOLDERS' EQUITY Accounts payable Accrued expenses: Salaries and wages Vacation ESOP payable Other Payroll and other taxes withheld Contract liabilities Total current liabilities Liabilities, Current Deferred tax liabilities Deferred tax liabilities as of the balance sheet date. Total liabilities Liabilities Commitments and contingencies (see Note 5) Common stock, par value $.33-1/3 per share Authorized 10,000,000 shares; Issued 3,129,874 shares as of September 30, 2021 and June 30, 2021. Outstanding 2,702,633 shares as of September 30, 2021 and June 30, 2021 (includes 273,645 and 279,429 Unearned ESOP shares, respectively) Capital in excess of par value Accumulated other comprehensive loss Retained earnings Total stockholders equity before ESOP Total of all stockholders' equity (deficit) items, before ESOP and Treasury stock. TotalStockholdersEquityBeforyEsopAndTreasuryStock [Default Label] Less: Unearned ESOP shares Unearned ESOP shares. UnearnedEsopSharesCost Cost of 427,241 shares of common stock in treasury as of September 30, 2021 and June 30, 2021 Treasury Stock, Value Total stockholders' equity Balance, beginning Balance, ending Stockholders' Equity Attributable to Parent Total liabilities and stockholders' equity Liabilities and Equity Trade accounts receivable, allowance Common stock, par value Common stock, shares authorized Common stock, shares issued Common stock, shares outstanding Balance, beginning, shares Balance, ending, common shares Unearned ESOP, shares Treasury stock, shares Income Statement [Abstract] Net sales Revenue Cost of sales Gross profit Gross Profit Selling, general and administrative expenses Operating income Operating Income (Loss) Other income Interest income Other Other Nonoperating Income Total other income Nonoperating Income (Expense) Income before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Net income Net income Other comprehensive income, net of tax Unrealized loss on investment securities Other comprehensive income (loss), net of tax Total comprehensive income Total comprehensive income (loss) Net income per share: Basic Diluted Weighted average number of shares outstanding: Basic Weighted Average Number of Shares Outstanding, Basic Diluted Weighted Average Number of Shares Outstanding, Diluted Dividends per share: Statement [Table] Equity Components [Axis] Common Stock [Member] Capital in Excess of Par Value [Member] Accumulated Other Comprehensive (Loss) Income [Member] Retained Earnings [Member] Treasury Stock [Member] Unearned ESOP Shares [Member] Information pertaining to unearned employee stock ownership plan shares. Statement [Line Items] Comprehensive income: Stock-based compensation Dividends declared on common stock per share Dividends, Common Stock, Cash Stock Transactions, Parenthetical Disclosures [Abstract] Other comprehensive income (loss), tax portion Dividends declared per share Cash divided paid Statement of Cash Flows [Abstract] Cash Flows from Operating Activities: Adjustments to reconcile net income to net cash provided by operating activities: Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Depreciation ESOP compensation expense Deferred income tax benefit Changes in assets and liabilities: Decrease in trade accounts receivable Increase (Decrease) in Accounts Receivable Decrease (increase) in income taxes receivable Increase (Decrease) in Income Taxes Receivable Decrease (increase) in inventories Increase (Decrease) in Inventories Decrease (increase) in prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Decrease in accounts payable Increase in accrued salaries and wages Decrease in vacation accrual The increase (decrease) in vacation accrual for the period. Increase (decrease) in other accrued expenses Increase in payroll and other taxes withheld Increase in contract liabilities Decrease in income taxes payable Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Investing Activities: Additions to property, plant and equipment Payments to Acquire Property, Plant, and Equipment Purchase of investment securities Payments to Acquire Debt Securities, Available-for-sale Proceeds from sale/maturity of investment securities Net cash (used in) provided by investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities: Dividends on common stock Payments of Ordinary Dividends, Common Stock Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Increase in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Supplemental Schedule of Cash Flow Information: Income taxes paid Supplemental Schedule of Non-cash Financing Activities: Accrual of dividends Represents the amount of dividends accrued in noncash investing or financing activities. Basis of Presentation [Abstract] Basis of Presentation Investments, Debt and Equity Securities [Abstract] Investment Securities Net Income per Share [Abstract] Net (Loss) Income per Share Share-based Payment Arrangement [Abstract] Stock Based Compensation Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Revenue from Contract with Customer [Abstract] Revenue Recently Issued Accounting Standards [Abstract] Recently Issued Accounting Standards Employee Stock Ownership Plan [Abstract] Employee Stock Ownership Plan The entire disclosure for employee stock ownership plan. Schedule of Available-for-Sale Securities Schedule of Contractual Maturities Schedule of Fair Value Assumptions Schedule of Stock Option Activity Schedule of Changes in Non-Vested Stock Options Schedule of ESOP shares Schedule of Available-for-sale Securities [Table] Financial Instrument [Axis] Certificates of Deposit [Member] Debt Securities, Available-for-sale [Line Items] Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Contractual maturities of available-for-sale securities Less than One Year One to Five Years Anti-dilutive securities Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Non-qualified stock options [Member] Non-qualified stock options [Member] Incentive Stock Options [Member] Incentive Stock Options [Member] Stock Option Plans [Member] Plan Name [Axis] 2017 Plan [Member] 2017 Plan [Member] 2007 Plan [Member] Name of the equity-based compensation arrangement plan. Award Type [Axis] Title of Individual [Axis] Non employee directors [Member] Non employee directors [Member] Individual Employee [Member] Individual Employee [Member] Range [Axis] Statistical Measurement [Axis] Maximum [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Stock based compensation expense Deferred tax benefit related to stock based compensation Unrecognized compensation costs