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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