Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 14,741	$ 23,740	$ 6,046
Adjustments to reconcile net income to net cash provided by operating activities, net of assets acquired and liabilities assumed:
Depreciation and amortization	13,981	17,311	21,274
Provision for receivable allowances	6,795	8,935	8,563
Write-down of marketable equity securities	454	1,903	7
Net change in inventory provision	1,576	2,852	1,724
Stock-based compensation	3,343	2,867	2,785
Deferred income taxes	$ 3,768	1,340	(551)
Tax impacts due to employee equity incentive plans		(105)	(152)
Foreign currency adjustments on intercompany amounts and other non-cash items	$ 214	(5,033)	312
Changes in operating assets and liabilities, net of business acquired:
Accounts receivable	(2,238)	(7,342)	(14,755)
Inventories	(7,702)	(2,203)	(6,296)
Prepaid expenses and other current assets	(1,219)	5,103	(5,518)
Other assets	(101)	828	(968)
Accounts payable	(2,173)	(2,646)	2,067
Accrued expenses and other liabilities	(693)	2,058	5,698
Pension liabilities	(1,153)	(1,414)	(907)
Net cash provided by operating activities	29,593	48,194	19,329
Cash flows from investing activities:
Change in restricted cash	88	71	(23)
Purchase of businesses, net of cash and cash equivalents acquired and installment payments	(14,571)	(2,297)	$ (20,000)
Purchases of investments	(629)	(5,887)
Purchases of plant and equipment	(7,110)	(7,018)	$ (7,623)
Proceeds from sale of investments	26	54	512
Net cash used in investing activities	(22,196)	(15,077)	(27,134)
Cash flows from financing activities:
Principal payments on capital lease obligations	(472)	(2,414)	(2,570)
Repayments of loans and notes payable	$ (47,606)	(1,144)	$ (1,000)
Installment payments for business acquisition		(30,000)
Proceeds from loans	$ 82,967	30,000
Tax impacts due to employee equity incentive plans		$ 105	$ 152
Purchases of treasury stock	$ (8,352)		(602)
Payments of cash dividends to stockholders	(4,896)	$ (4,263)	(3,744)
Proceeds from employee equity plans	4,336	2,587	4,420
Net cash provided by (used in) financing activities	25,977	(5,129)	(3,344)
Effect of exchange rate fluctuations on cash and cash equivalents	1,268	(5,262)	2,471
Net increase (decrease) in cash and cash equivalents	34,642	22,726	(8,678)
Cash and cash equivalents at beginning of the year	121,164	98,438	107,116
Cash and cash equivalents at end of the year	155,806	121,164	98,438
Supplemental disclosure of cash flow information
Cash paid during the period for interest	1,992	2,172	801
Cash paid during the period for income taxes	$ 5,669	$ 1,416	$ 4,760