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Note A - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)			3 Months Ended		12 Months Ended
	Sep. 30, 2017 USD ($)	Aug. 07, 2017 shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($) shares	Jun. 30, 2018 USD ($)
Sales Discounts, Noncash			$ 245,000	$ 163,000
Royalty and Licensing Revenue			5,400,000	5,900,000
Royalty Expense			263,000	284,000
Notes, Loans and Financing Receivable, Net, Current, Total			1,500,000		$ 1,500,000
Investment Income, Interest			$ 555,000	$ 250,000
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, Forfeitures in Period \| shares			0	0
Allocated Share-based Compensation Expense, Total			$ 409,000	$ 301,000
Foreign Currency Contract, Asset, Fair Value Disclosure			$ 1,000,000		55,000
Foreign Currency Contracts, Liability, Fair Value Disclosure					$ 55,000
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration of Risk Number of Major Customers			3
Concentration Risk, Percentage			67.60%		76.60%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Beta Alanine Raw Material Sale Customers [Member]
Concentration Risk, Percentage			20.40%		17.30%
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
Juice Plus + [Member]
Agreement, Term		5 years
Kaged Muscle LLC [Member] \| Notes Receivable [Member]
Notes, Loans and Financing Receivable, Term	1 year
Notes, Loans and Financing Receivable, Net, Current, Total	$ 1,500,000			$ 1,500,000
Notes, Loans and Financing Receivable, Extension Fee			25,000
Notes, Loans and Financing Receivable, Interest Rate, Stated Percentage	15.00%			15.00%
Investment Income, Interest			$ 58,000	$ 0
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares			15,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares			15,000	0
Restricted Stock [Member] \| Juice Plus + [Member]
Stock Issuance Agreement, Shares Agreed to Grant \| shares		500,000
Sales Discounts, Noncash			$ 245,000	$ 163,000
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares			0	0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.00%