Restatement of Previously Issued Financial Statements - Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Nov. 30, 2017	Nov. 30, 2016	Nov. 30, 2017	Nov. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net Income	$ (166)	$ 16,646	$ 21,682	$ 48,994
Deferred income taxes			2,362	(538)
Inventories			(11,744)	(6,795)
Net change in billings related to costs and estimated earnings on uncompleted contracts			4,896	(3,277)
Other accrued liabilities and income taxes payable			(9,191)	(956)
Net cash (used in) provided by operating activities:			$ 38,710	57,275
As Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net Income		18,251		49,337
Deferred income taxes				(331)
Inventories				(20,760)
Net change in billings related to costs and estimated earnings on uncompleted contracts				8,853
Other accrued liabilities and income taxes payable				329
Net cash (used in) provided by operating activities:				57,275
Correction
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net Income		$ (1,605)		(343)
Deferred income taxes				(207)
Inventories				13,965
Net change in billings related to costs and estimated earnings on uncompleted contracts				(12,130)
Other accrued liabilities and income taxes payable				(1,285)
Net cash (used in) provided by operating activities:				$ 0