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Note A - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)		3 Months Ended		6 Months Ended		12 Months Ended
	Aug. 07, 2017 shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Jun. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)
Sales Discounts, Noncash				$ 408,000
Royalty and Licensing Revenue		$ 4,000,000	$ 6,700,000	9,800,000	13,400,000
Royalty Expense		160,000	250,000	444,000	566,000
Notes, Loans and Financing Receivable, Net, Current		1,500,000		1,500,000
Investment Income, Interest		$ 304,000	$ 133,000	$ 554,000	$ 249,000
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		$ 302,000	$ 256,000	$ 603,000	$ 506,000
Foreign Currency Contracts, Liability, Fair Value Disclosure		2,700,000		$ 2,700,000		$ 521,000
Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Concentration of Risk Number of Major Customers				3	3
Concentration Risk, Percentage				76.10%		65.60%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Beta Alanine Raw Material Sale Customers [Member]
Concentration Risk, Percentage				15.60%		21.30%
Fair Value, Inputs, Level 1 [Member]
Fair Value, Net Asset (Liability)		0		$ 0		$ 0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Net Asset (Liability)		0		0		$ 0
Juice Plus + [Member]
Agreement, Term	5 years
Kaged Muscle LLC [Member] \| Notes Receivable [Member]
Notes, Loans and Financing Receivable, Net, Current							$ 1,500,000
Notes, Loans and Financing Receivable, Interest Rate, Stated Percentage							1500.00%
Investment Income, Interest		$ 58,000		$ 58,000
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares		135,000	0	0	0
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares		813,665	0	0	0
Restricted Stock [Member] \| 2009 Omnibus Stock Incentive Plan [Member] \| Employees [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross \| shares		0	0	0
Restricted Stock [Member] \| 2009 Omnibus Stock Incentive Plan [Member] \| Management [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross \| shares				10,000
Restricted Stock [Member] \| Juice Plus + [Member]
Stock Issuance Agreement, Shares Agreed to Grant \| shares	500,000
Sales Discounts, Noncash		$ 245,000		$ 408,000