Note I - Income Taxes (Detail) - Significant Components of the Company’s Deferred Tax Assets and Liabilities (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Valuation allowance:
Net deferred tax asset	$ 2,308	$ 2,914
Depreciation [Member]
Liabilities:
Deferred Income Tax Liabilities	(3,887)	(3,808)
Other Tax [Member]
Liabilities:
Deferred Income Tax Liabilities	(451)	(430)
Total [Member]
Liabilities:
Deferred Income Tax Liabilities	(4,338)	(4,238)
State and Local Jurisdiction [Member]
Assets:
Deferred Income Tax Assets	9,620	5,242
Bad Debt Reserves [Member]
Assets:
Deferred Income Tax Assets	391	454
Inventory Valuation Reserve [Member]
Assets:
Deferred Income Tax Assets	2,951	2,959
Sales Return Reserve [Member]
Assets:
Deferred Income Tax Assets	546	686
Stock Compensation Plan [Member]
Assets:
Deferred Income Tax Assets	4,374	3,969
Foreign Research And Development Credit [Member]
Assets:
Deferred Income Tax Assets	33	28
Alternative Minimum Tax Credit And US Foreign Tax Credit [Member]
Assets:
Deferred Income Tax Assets	4,254	3,660
Palladium Contingent Purchase Price [Member]
Assets:
Deferred Income Tax Assets	61	77
Federal Net Operating Losses [Member]
Assets:
Deferred Income Tax Assets	41,601	30,998
Foreign Net Operating Losses [Member]
Assets:
Deferred Income Tax Assets	1,914	2,341
Other Tax [Member]
Assets:
Deferred Income Tax Assets	2,538	2,257
Total [Member]
Assets:
Deferred Income Tax Assets	68,283	52,671
United States [Member]
Valuation allowance:
Valuation Allowances	(61,062)	(45,147)
Foreign [Member]
Valuation allowance:
Valuation Allowances	(575)	(372)
Total [Member]
Valuation allowance:
Valuation Allowances	$ (61,637)	$ (45,519)