OPERATIONS, BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Inventory Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Impairment of inventories	$ 9,276	$ 5,717	$ 7,572
Inventory Valuation Reserve
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance – beginning of fiscal year	26,030	21,514	27,763
Impairment of inventories	0	0	7,572
Additional allowances	2,140	6,355	1,617
Inventory disposed and scrapped	(7,427)	(3,353)	(14,635)
Foreign currency effects	(1,295)	1,514	(803)
Balance – end of fiscal year	$ 19,448	$ 26,030	$ 21,514