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Note A - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, € in Millions |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Aug. 07, 2017 shares | Jun. 30, 2018 USD ($) $ / shares shares | Jun. 30, 2017 USD ($) $ / shares shares | Jun. 30, 2018 EUR (€) shares | Sep. 30, 2017 USD ($)
Foreign Currency Contract, Asset, Fair Value Disclosure |  | $ 55,000 |  |  |
Foreign Currency Contracts, Liability, Fair Value Disclosure |  | 55,000 | $ 521,000 |  |
Notes, Loans and Financing Receivable, Net, Current, Total |  | 1,500,000 |  |  |
Investment Income, Interest |  | 1,085,000 | 459,000 |  |
Impairment of Long-Lived Assets to be Disposed of |  | 0 | 0 |  |
Sales Discounts, Noncash |  | 898,000 |  |  |
Royalty and Licensing Revenue |  | 21,400,000 | 26,900,000 |  |
Royalty Expense |  | 854,000 | 1,000,000 |  |
Research and Development Expense, Total |  | 1,500,000 | 1,600,000 |  |
Advertising Expense |  | 2,400,000 | 598,000 |  |
Liability for Uncertainty in Income Taxes, Current |  | 0 | $ 0 |  |
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount |  | $ 0 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares |  | 0 | 0 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  | 0 | 0 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  | $ 0 | $ 0 |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |  |  |  |
Concentration of Risk Number of Major Customers |  | 3 |  |  |
Concentration Risk, Percentage |  | 76.60% | 65.60% |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Beta Alanine Raw Material Sale Customers [Member] |  |  |  |  |
Concentration Risk, Percentage |  | 17.30% | 21.30% |  |
2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] |  |  |  |  |
Stock Issued During Period, Shares, Restricted Stock Award, Gross | shares |  | 175,000 | 155,000 |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance | shares |  | 458,012 | 319,355 | 458,012 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options |  | $ 3,100,000 |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  | 2 years 219 days |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  | $ 10.19 | $ 8.82 |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  | 41,661 | 0 |  |
Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  | $ 11.30 |  |  |
Employee Stock Option [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  | 0.00% |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  |  | 0 |  |
Foreign Exchange Contract [Member] |  |  |  |  |
Derivative, Notional Amount |  | $ 34,400,000 |  | € 29 |
Derivative, Remaining Maturity |  | 1 year 60 days |  |  |
Minimum [Member] |  |  |  |  |
Property, Plant and Equipment, Useful Life |  | 1 year |  |  |
Minimum [Member] | Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 3 years |  |  |
Maximum [Member] |  |  |  |  |
Property, Plant and Equipment, Useful Life |  | 39 years |  |  |
Maximum [Member] | Restricted Stock [Member] | 2009 Omnibus Stock Incentive Plan [Member] | Board of Directors and Management Members [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 5 years |  |  |
Kaged Muscle LLC [Member] | Notes Receivable [Member] |  |  |  |  |
Notes, Loans and Financing Receivable, Net, Current, Total |  |  |  |  | $ 1,500,000
Notes, Loans and Financing Receivable, Interest Rate, Stated Percentage |  |  |  |  | 15.00%
Investment Income, Interest |  | $ 171,000 |  |  |
Juice Plus + [Member] |  |  |  |  |
Agreement, Term | 5 years |  |  |  |
Juice Plus + [Member] | Restricted Stock [Member] |  |  |  |  |
Stock Issuance Agreement, Shares Agreed to Grant | shares | 500,000 |  |  |  |
Sales Discounts, Noncash |  | 898,000 |  |  |
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |
Fair Value, Net Asset (Liability), Total |  | 0 | $ 0 |  |
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |
Fair Value, Net Asset (Liability), Total |  | $ 0 | $ 0 |  |

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