Note 1 - Organization and Summary of Significant Accounting Policies 1 (Details Textual) $ in Thousands	3 Months Ended										12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)		Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	[2]	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)
Net Cash Provided by (Used in) Investing Activities, Total											$ 63,017	$ (35,650)	$ (24,653)
Net Cash Provided by (Used in) Financing Activities, Total											(49,256)	(33,941)	(34,072)
Foreign Currency Transaction Gain (Loss), before Tax, Total											(453)	(135)	22
Goodwill, Impairment Loss											0	0	0
Revenue from Contract with Customer, Excluding Assessed Tax, Total	$ 102,896	$ 94,231	$ 86,285	$ 82,223	$ 86,531	[1]	$ 78,009	$ 69,814	$ 60,136		365,635	294,490	348,201
Cost of Goods and Services Sold, Total											152,814	129,345	151,698
Inventory, Net, Total	55,013				33,052						55,013	33,052
Reimbursements from Research and Development Contracts											$ 0	$ 0	$ 3,000
Effective Income Tax Rate Reconciliation, at Highest Federal Statutory Income Tax Rate, Percent													35.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent											21.00%	21.00%	34.00%
Tax Cuts and Jobs Act, Transition Tax for Accumulated Foreign Earnings, Liability, Total	0										$ 0
Number of Reportable Segments											1	1	1
Licenses for Intellectual Property [Member]
Percent of Revenue From Nonproduct Sales											7.00%	3.00%	3.00%
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life											1 year
Product Warranty Term											1 year
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life											10 years
Product Warranty Term											2 years
Accounting Standards Update 2016-01 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption					0							$ 0		$ 0
Accounting Standards Update 2014-09 [Member]
Revenue from Contract with Customer, Excluding Assessed Tax, Total												3,778
Cost of Goods and Services Sold, Total												779
Deferred Revenue, Total					3,778							3,778
Inventory, Net, Total					779							779
Contract with Customer, Refund Liability, Total	$ 656				$ 1,634						$ 656	1,634
Revision [Member]
Net Cash Provided by (Used in) Investing Activities, Total												21,311	$ 13,688
Net Cash Provided by (Used in) Financing Activities, Total												(21,311)	(13,688)
Previously Reported [Member]
Net Cash Provided by (Used in) Investing Activities, Total												(56,961)	(38,341)
Net Cash Provided by (Used in) Financing Activities, Total												$ (12,630)	$ (20,384)

[1] The Company recorded a charge of $7,000 due to impairment of a non-marketable equity investment.

[2] The benefit for income taxes included partial release of federal valuation allowance resulting from the transfer of an acquired in-process research and development to developed technology in 2018 which allowed the related deferred tax liability to be considered a source of income for realizing deferred tax assets, as well as the revaluation of the foreign deferred tax liability on the in-process research and development based on the foreign tax rates applicable to the anticipated reversal periods.