Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Operating activities:
Net income	$ 22,065,000	$ 8,984,000	$ 19,579,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	36,136,000	25,162,000	20,531,000
Deferred income taxes and related valuation allowance	19,968,000	489,000	7,336,000
Loss on sale of real estate/investments and other	47,000	14,000	34,000
Payment for Debt Extinguishment or Debt Prepayment Cost	619,000	1,303,000	0
Impairment of tangible assets	0	0	429,000
Amortization of deferred financing costs and discount on debt	2,681,000	1,015,000	600,000
Stock-based compensation	5,586,000	5,914,000	4,063,000
Amortization of Acquisition Costs	0	8,852,000	0
Foreign Currency Transaction Loss, before Tax	0	1,590,000	0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	0	1,125,000	0
Changes in operating assets and liabilities, net of effects of business acquisitions and divestitures:
Trade accounts receivable	(9,308,000)	(785,000)	12,409,000
Inventories	(12,249,000)	8,173,000	2,483,000
Prepaid expenses and other	(1,727,000)	(6,121,000)	375,000
Other assets	(3,338,000)	3,044,000	(3,179,000)
Trade accounts payable	3,833,000	1,002,000	(5,308,000)
Accrued liabilities	11,918,000	(2,380,000)	(5,799,000)
Non-current liabilities	(16,700,000)	(3,085,000)	(6,516,000)
Net cash provided by operating activities	69,661,000	60,450,000	52,645,000
Investing activities:
Proceeds from sales of marketable securities	653,000	12,336,000	5,869,000
Purchases of marketable securities	(327,000)	(1,571,000)	(4,311,000)
Capital expenditures	(14,515,000)	(14,368,000)	(22,320,000)
Payments for Derivative Instrument, Investing Activities	0	(1,590,000)	0
Payments to Acquire Businesses, Net of Cash Acquired	0	(218,846,000)	(182,467,000)
Payments to Acquire Long-term Investments	(3,359,000)	0	0
Payments for (Proceeds from) Other Investing Activities	(14,750,000)	0	0
Net Cash Provided by (Used in) Investing Activities	(32,298,000)	(224,039,000)	(203,229,000)
Financing activities:
Proceeds from the issuance of common stock	6,332,000	50,439,000	242,000
Payments of Dividends	(3,658,000)	(3,326,000)	(3,212,000)
Increase (Decrease) in Restricted Cash	0	(588,000)	0
Net borrowings (repayments) under lines of credit	0	(155,000,000)	154,057,000
Repayment of debt	(60,144,000)	(125,730,000)	(13,187,000)
Proceeds from (Repayments of) Other Long-term Debt	0	445,000,000	0
Fees related to debt repricing/refinancing and equity offerings	(619,000)	(19,409,000)	0
Other	(1,413,000)	(1,265,000)	(897,000)
Net cash (used for) provided by financing activities	(59,502,000)	190,121,000	137,003,000
Effect of exchange rate changes on cash	7,569,000	(544,000)	2,128,000
Net change in cash and cash equivalents	(14,570,000)	25,988,000	(11,453,000)
Cash and cash equivalents at beginning of year	77,591,000	51,603,000	63,056,000
Cash and cash equivalents at end of year	63,021,000	77,591,000	51,603,000
Supplementary cash flows data:
Interest paid	18,914,000	10,633,000	7,649,000
Income taxes paid, net of refunds	706,000	1,893,000	4,175,000
Property, plant and equipment purchases included in trade accounts payable	0	0	1,638,000
Decrease in Restricted Cash	$ 294,000	$ 0	$ 822,000