Note 6 - Balance Sheet Details (Tables)

12 Months Ended

Mar. 31, 2017

Notes Tables

Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]

	March 31,
	2017			2016
Accounts receivable, gross	$	45,856		$	41,219
Allowances		(4,689	)		(2,779	)
Accounts receivable, net	$	41,167		$	38,440

Schedule of Allowance Movement [Table Text Block]

	Balance at Beginning of Year		Additions		Utilization			Translation Adjustments			Balance at End of Year
Allowances for accounts receivable and for doubtful accounts:
Year ended March 31, 2017	$	2,779	$	10,608	$	(8,657	)	$	(41	)	$	4,689
Year ended March 31, 2016	$	2,768	$	6,795	$	(6,799	)	$	15		$	2,779
Year ended March 31, 2015	$	3,013	$	8,935	$	(9,004	)	$	(176	)	$	2,768

Schedule of Inventory, Current [Table Text Block]

	March 31,
	2017		2016
Raw materials	$	17,920	$	18,269
Work in process		45,634		41,549
Finished goods		25,882		29,786
Total	$	89,436	$	89,604

Property, Plant and Equipment [Table Text Block]

	March 31,
	2017			2016
Property and plant (useful life of 24 years to 50 years)	$	38,195		$	35,290
Equipment owned (useful life of 2 to 8 years)		137,105			139,318
Leasehold improvements (useful life of up to 40 years)		1,064			1,304
Property, plant and equipment, gross		176,364			175,912
Accumulated depreciation		(134,124	)		(133,289	)
Property, plant and equipment, net	$	42,240		$	42,623

Schedule of Accrued Liabilities [Table Text Block]

	March 31,
	2017		2016
Uninvoiced goods and services	$	12,703	$	8,824
Compensation and benefits		6,707		7,540
Income taxes		3,521		2,066
Commissions, royalties and other		2,416		2,860
Total	$	25,347	$	21,290