Schedule II - Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Mar. 31, 2011
Accounts Receivable - Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 968,000	[1]	$ 1,049,000	[1]	$ 1,141,000
Charged to cost and expense	659,000
Amounts written off	37,000		65,000	[1]	77,000
Amounts recovered			(16,000)	[1]	(38,000)
Balance at end of period before adjustment					1,026,000
Balance at end of period	1,590,000		968,000	[1]	1,049,000	[1]
Valuation allowances and reserves, reserves of businesses acquired	23,000
Accounts Receivable - Allowance for Customer-Payment Discrepancies [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	280,000		648,000		553,000
Charged to cost and expense	2,035,000		270,000		850,000
Amounts written off			638,000		755,000
Amounts recovered	(235,000)
Balance at end of period	2,550,000		280,000		648,000
Inventory - Allowance for Excess and Obsolete Inventory [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	11,308,000	[2]	14,736,000	[2]	2,480,000
Charged to cost and expense	17,383,000		3,012,000	[2]	1,804,000
Amounts written off	3,698,000		6,440,000	[2]	1,685,000
Balance at end of period before adjustment					2,599,000
Balance at end of period	24,993,000		11,308,000	[2]	14,736,000	[2]
Valuation allowances and reserves, reserves of businesses acquired	$ 12,137,000

[1] Includes $23,000 of allowance for doubtful accounts established in the opening balance sheet in connection with the Company's May 6, 2011 acquisition

[2] Includes $12,137,000 of allowance for excess and obsolete inventory established in the opening balance sheet in connection with the Company's May 6, 2011 acquisition.