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Note A - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual) - USD ($)				3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Aug. 07, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
Sales Discounts, Noncash						$ 490,000	$ 408,000
Royalty and Licensing Revenue				$ 4,400,000	$ 4,000,000	9,800,000	9,800,000
Royalty Expense				178,000	160,000	441,000	444,000
Notes, Loans and Financing Receivable, Net, Current, Total								$ 1,500,000
Investment Income, Interest				$ 529,000	$ 304,000	$ 1,084,000	$ 554,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				0	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				0	0	5,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period				0	0	0	5,000
Allocated Share-based Compensation Expense, Total				$ 400,000	$ 302,000	$ 809,000	$ 603,000
Foreign Currency Contract, Asset, Fair Value Disclosure				2,500,000		$ 2,500,000		55,000
Foreign Currency Contracts, Liability, Fair Value Disclosure								$ 55,000
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk, Percentage						73.00%		76.60%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Beta Alanine Raw Material Sale Customers [Member]
Concentration Risk, Percentage						11.90%		17.30%
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, Term		1 year
Notes, Loans and Financing Receivable, Net, 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				$ 46,000	$ 58,000	$ 104,000	$ 58,000
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount				0	813,665	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				0	0	15,000	0
Restricted Stock [Member] \| Juice Plus + [Member]
Stock Issuance Agreement, Shares Agreed to Grant			500,000
Sales Discounts, Noncash				$ 245,000	$ 245,000	$ 490,000	$ 408,000
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount				0	135,000	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate						0.00%