Income Taxes Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Feb. 28, 2017	Feb. 28, 2019	Feb. 28, 2018
Components of Deferred Tax Assets and Liabilities [Abstract]
Deferred Tax Assets, Other		$ 357	$ 52
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		6,164
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 6,588	6,164	(2,546)
Inventory		2,374	2,011
Property, plant and equipment		1,900	479
Accruals and reserves		4,008	2,375
Deferred compensation		632	806
Warranty reserves		699	976
Deferred Tax Assets, Unrealized Gains (Losses)		4,179	1,335
Deferred Tax Assets, Investments		496	0
Foreign and state operating losses		12,267	13,191
Foreign tax credits		3,805	4,501
Other tax credits		4,752	3,530
Deferred tax assets before valuation allowance		35,469	29,256
Less: valuation allowance		(22,026)	(15,881)
Net deferred tax assets		13,443	13,375
Intangible assets		(17,145)	(23,157)
Deferred Tax Liabilities, Investments		0	(100)
Prepaid expenses		(1,286)	(1,995)
Deferred financing fees		(217)	(316)
Total deferred tax liabilities		18,648	25,568
Deferred Tax Liabilities, Net		5,205	$ 12,193
Deferred Tax Assets, Operating Loss Carryforwards, Domestic		40,777
Tax Credit Carryforward, Amount		3,804
Deferred Tax Assets, Tax Credit Carryforwards, Research		$ 2,742