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Note A - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 07, 2017 shares	Mar. 31, 2018 USD ($) shares	Mar. 31, 2017 USD ($) shares	Mar. 31, 2018 USD ($) shares	Mar. 31, 2017 USD ($) shares	Jun. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)
Sales Discounts, Noncash				$ 653,000
Royalty and Licensing Revenue		$ 6,200,000	$ 6,600,000	16,000,000	20,000,000
Royalty Expense		215,000	233,000	659,000	799,000
Notes, Loans and Financing Receivable, Net, Current, Total		1,556,000		1,556,000
Investment Income, Interest		$ 269,000	$ 109,000	$ 823,000	$ 358,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross \| shares		0	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period \| shares		0	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period \| shares		0	0	5,000	0
Allocated Share-based Compensation Expense, Total		$ 322,000	$ 223,000	$ 925,000	$ 729,000
Foreign Currency Contracts, Liability, Fair Value Disclosure		3,100,000		$ 3,100,000		$ 521,000
Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Concentration of Risk Number of Major Customers				3		3
Concentration Risk, Percentage				65.40%		65.60%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Beta Alanine Raw Material Sale Customers [Member]
Concentration Risk, Percentage				26.10%		21.30%
Fair Value, Inputs, Level 1 [Member]
Fair Value, Net Asset (Liability), Total		0		$ 0		$ 0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Net Asset (Liability), Total		0		0		$ 0
Juice Plus + [Member]
Agreement, Term	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		$ 56,000		$ 114,000
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares		175,000	0	175,000	0
Restricted Stock [Member] \| Directors and Key Members of Management Team [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares		175,000	140,000	175,000	150,000
Restricted Stock [Member] \| Juice Plus + [Member]
Stock Issuance Agreement, Shares Agreed to Grant \| shares	500,000
Sales Discounts, Noncash		$ 245,000		$ 653,000