DETAILS OF CERTAIN BALANCE SHEET ACCOUNTS (Details) (USD $)	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Mar. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	$ 128,961,000		$ 128,961,000		$ 133,233,000
Accounts receivable, net	108,070,000		108,070,000		111,771,000
Inventory, net [Abstract]
Raw materials	28,438,000		28,438,000		21,246,000
Work in process	551,000		551,000		367,000
Finished goods	32,650,000		32,650,000		32,100,000
Inventory, Net	61,639,000		61,639,000		53,713,000
Property, Plant and Equipment, Net [Abstract]
Land	13,961,000		13,961,000		6,531,000
Buildings and improvements	71,746,000		71,746,000		67,417,000
Machinery and equipment	84,617,000		84,617,000		90,643,000
Software	29,116,000		29,116,000		28,951,000
Construction in progress	4,968,000		4,968,000		2,323,000
Property, Plant and Equipment, Gross	204,408,000		204,408,000		195,865,000
Accumulated depreciation and amortization	(114,642,000)		(114,642,000)		(119,706,000)
Property, plant and equipment, net	89,766,000		89,766,000		76,159,000
Depreciation and amortization	4,000,000	3,300,000	7,700,000	6,500,000
Unamortized capitalized computer software costs	6,000,000		6,000,000		6,700,000
Accrued Liabilities [Abstract]
Employee compensation and benefits	24,044,000		24,044,000		24,458,000
Warranty obligation	12,722,000		12,722,000		13,346,000
Accrued advertising and sales and marketing	2,335,000		2,335,000		1,152,000
Accrued other	14,348,000		14,348,000		13,111,000
Accrued liabilities	53,449,000		53,449,000		52,067,000
Changes in the Warranty Obligation [Roll Forward]
Warranty obligation at March 31, 2012			13,346,000
Warranty provision relating to products shipped			7,440,000
Deductions for warranty claims processed			(8,064,000)
Warranty obligation at September 30, 2012	12,722,000		12,722,000
Capitalized Computer Software, Amortization			1,500,000	1,600,000
Buildings and improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			7 years
Buildings and improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			30 years
Machinery and equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			2 years
Machinery and equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			10 years
Software [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			5 years
Software [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Estimated Useful Lives			6 years
Provision For Returns [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Reserves	(7,681,000)		(7,681,000)		(7,613,000)
Provision For Promotions, Rebates And Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Reserves	(12,790,000)		(12,790,000)		(12,756,000)
Provision For Doubtful Accounts And Sales Allowances [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable Reserves	$ (420,000)		$ (420,000)		$ (1,093,000)