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Note A - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, € in Millions |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2017 USD ($) | Aug. 07, 2017 shares | Sep. 30, 2019 USD ($) | Dec. 28, 2018 USD ($) | Jun. 30, 2019 USD ($) $ / shares shares | Jun. 30, 2018 USD ($) $ / shares shares | Jul. 01, 2019 USD ($) | Jun. 30, 2019 EUR (€) shares
Foreign Currency Contract, Asset, Fair Value Disclosure |  |  |  |  | $ 2,300,000 | $ 55,000 |  |
Foreign Currency Contracts, Liability, Fair Value Disclosure |  |  |  |  |  | 55,000 |  |
Financing Receivable, after Allowance for Credit Loss, Current, Total |  |  |  |  |  | 1,500,000 |  |
Investment Income, Interest |  |  |  |  | 1,868,000 | 1,085,000 |  |
Inventory Valuation Reserves, Ending Balance |  |  |  |  | 1,106,000 | 372,000 |  |
Impairment of Long-Lived Assets to be Disposed of |  |  |  |  | 0 | 0 |  |
Sales Discounts, Noncash |  |  |  |  | 82,000 | 898,000 |  |
Sales, Royalty and Licensing Revenue |  |  |  |  | 16,700,000 | 21,400,000 |  |
Royalty Expense |  |  |  |  | 686,000 | 854,000 |  |
Research and Development Expense, Total |  |  |  |  | 1,800,000 | 1,500,000 |  |
Advertising Expense |  |  |  |  | $ 1,600,000 | $ 2,400,000 |  |
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 |  |  |  |  | 5,000 | 0 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  |  |  |  | $ 0 | $ 0 |  |
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Beta Alanine Raw Material Sale Customers [Member] |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  | 8.00% | 17.30% |  |
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Three Customers [Member] |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  | 76.80% | 76.60% |  |
Restricted Stock 1 [Member] |  |  |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  |  |  |  | 0 | 41,661 |  |
The 2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | shares |  |  |  |  | 1,400,000 |  |  | 1,400,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | shares |  |  |  |  | 229,000 |  |  | 229,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares |  |  |  |  | 5,000 |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  |  |  | 190,000 | 175,000 |  |
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount |  |  |  |  | $ 3,500,000 |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  |  |  |  | 2 years 109 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 |  |  |  |  | $ 11.57 | $ 11.30 |  |
Restricted Stock [Member] | The 2009 Omnibus Stock Incentive Plan [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  |  |  | 190,000 |  |  |
Restricted Stock [Member] | Juice Plus, Amended and Restated Exclusive Manufacturing Agreement [Member] |  |  |  |  |  |  |  |
Treasury Stock, Shares, Acquired | shares |  |  |  |  | 400,000 |  |  |
Share-based Payment Arrangement, Option [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  |  |  |  | 0.00% |  |  |
Foreign Exchange Contract [Member] |  |  |  |  |  |  |  |
Derivative, Notional Amount |  |  |  |  | $ 39,900,000 |  |  | € 32.5
Minimum [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  |  |  | 1 year |  |  |
Minimum [Member] | Restricted Stock [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] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  | 5 years |  |  |
SR CarnoSyn Powder [Member] |  |  |  |  |  |  |  |
Inventory Valuation Reserves, Ending Balance |  |  |  |  | $ 686,000 |  |  |
Kaged Muscle LLC [Member] | Notes Receivable [Member] |  |  |  |  |  |  |  |
Notes, Loans and Financing Receivable, Term | 1 year |  |  |  |  |  |  |
Financing Receivable, after Allowance for Credit Loss, Current, Total | $ 1,500,000 |  |  |  |  |  |  |
Notes, Loans and Financing Receivable, Extension Fee |  |  |  | $ 25,000 |  |  |  |
Notes, Loans and Financing Receivable, Interest Rate, Stated Percentage | 15.00% |  |  |  |  |  |  |
Investment Income, Interest |  |  |  |  | 104,000 | $ 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 |  |  |  |  | 82,000 | 898,000 |  |
Sales Discounts, Cash |  |  |  |  | 395,000 | 0 |  |
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Fair Value, Net Asset (Liability), Total |  |  |  |  | 0 | 0 |  |
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |  |  |
Fair Value, Net Asset (Liability), Total |  |  |  |  | 0 | 0 |  |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Cumulative Effect on Retained Earnings, Net of Tax, Total |  |  | $ 134,000 |  |  |  |  |
Nonoperating Income (Expense) [Member] |  |  |  |  |  |  |  |
Gain (Loss) on Derivative Instruments, Net, Pretax, Total |  |  |  |  | $ 1,600,000 | $ 900,000 |  |
Accounting Standards Update 2016-02 [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Operating Lease, Liability, Total |  |  |  |  |  |  | $ 20,400,000 |
Operating Lease, Right-of-Use Asset |  |  |  |  |  |  | $ 20,300,000 |

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