Description of Business and Summary of Significant Accounting Policies Product Warranty Table (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Feb. 28, 2017	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2017	Feb. 29, 2016
Standard Product Warranty Accrual	$ 5,608	$ 4,469	$ 6,233	$ 5,608	$ 7,608
Inventory Valuation Reserves		1,379	1,972
Standard and Extended Product Warranty Accrual, Additions from Business Acquisition	0	0	500
Standard Product Warranty Accrual, Increase for Warranties Issued	5,843	6,091	7,428
Standard Product Warranty Accrual, Period Increase (Decrease)		(832)	0	$ 0
Standard Product Warranty Accrual, Decrease for Payments	7,843	7,023	7,303
Product Warranty Expense	$ 5,843	6,091	7,428
SEC Schedule, 12-09, Reserve, Warranty [Member]
Standard Product Warranty Accrual		$ 3,090	$ 4,261

Amount of valuation reserve for inventory.

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Amount of increase in the standard and extended product warranty accrual from a business acquisition.

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The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

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Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

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Amount of increase (decrease) in the standard product warranty accrual. Excludes extended product warranties.

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Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

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