Schedule II - Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Accounts Receivable - Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 1,019,000	$ 947,000	$ 1,026,000
Charged to cost and expense	(47,000)	166,000	(14,000)
Amounts written off	118,000	94,000	65,000
Balance at end of period	854,000	1,019,000	947,000
Accounts Receivable - Allowance for Customer-Payment Discrepancies [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	514,000	280,000	648,000
Charged to cost and expense	(10,000)	536,000	270,000
Amounts written off		302,000	638,000
Amounts recovered	(73,000)
Balance at end of period	577,000	514,000	280,000
Inventory - Allowance for Excess and Obsolete Inventory [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	2,498,000	2,164,000	2,599,000
Charged to cost and expense	1,620,000	1,814,000	3,216,000
Amounts written off	1,410,000	1,480,000	3,651,000
Balance at end of period	$ 2,708,000	$ 2,498,000	$ 2,164,000

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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

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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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- Definition

Total of recoveries of amounts due the Entity that had previously been written off as uncollectible using allowances (the valuation accounts that are netted against the cost of an asset to value it at its carrying value) and total of reestablishments of reserves (liabilities established to represent expected future costs) that had previously been utilized.

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