Statements of Cash Flows Statement - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net Income (Loss) Attributable to Parent	$ 7,151	$ 13,939
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Amortization of Financing Costs and Discounts	0	1,017
Amortization	505	595
Depreciation	924	944
Foreign Currency Transaction Gain (Loss), before Tax	269	107
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Asset	132	117
Share-based Compensation	1,148	1,161
Provision for doubtful accounts and inventory valuation	951	800
Litigation Settlement, Amount	0	(14,632)
Increase (Decrease) in Other Operating Assets and Liabilities, Net	3,144	(10,067)
Net Cash Provided by (Used in) Operating Activities	14,224	(6,019)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Payments to Acquire Marketable Securities	(22,449)	(44,311)
Proceeds from Sale and Maturity of Marketable Securities	25,355	51,120
Payments to Acquire Property, Plant, and Equipment	(1,724)	(1,514)
Net Cash Provided by (Used in) Investing Activities	1,182	5,295
Net Cash Provided by (Used in) Financing Activities [Abstract]
Payments for Repurchase of Warrants	(1,025)	0
Payments for Repurchase of Common Stock	0	(4,700)
Payments Related to Tax Withholding for Share-based Compensation	(803)	(1,509)
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options	107	6
Net Cash Provided by (Used in) Financing Activities	(1,721)	(6,203)
Effect of Exchange Rate on Cash and Cash Equivalents	701	559
Cash and Cash Equivalents, Period Increase (Decrease)	14,386	(6,368)
Cash and Cash Equivalents, at Carrying Value	52,245	38,186
Supplemental Cash Flow Information [Abstract]
Income Taxes Paid	208	1,068
Interest Paid	$ 0	$ 1,125