Schedule II - Valuation and Qualifying Accounts (Details) - USD ($)	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Accounts Receivable - Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 629,000	$ 854,000	$ 1,019,000
Charged to cost and expense	4,404,000	184,000	(47,000)
Amounts written off	749,000	409,000	118,000
Balance at end of period	4,284,000	629,000	854,000
Accounts Receivable - Allowance for Customer-Payment Discrepancies [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	852,000	577,000	514,000
Charged to cost and expense	(299,000)	91,000	(10,000)
Amounts written off	(150,000)	(184,000)	(73,000)
Balance at end of period	703,000	852,000	577,000
Inventory - Allowance for Excess and Obsolete Inventory [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	2,675,000	2,708,000	2,498,000
Charged to cost and expense	4,518,000	1,635,000	1,620,000
Amounts written off	3,567,000	1,668,000	1,410,000
Balance at end of period	$ 3,626,000	$ 2,675,000	$ 2,708,000

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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