Note 10. Goodwill and Intangible Assets (Detail) (USD $)	1 Months Ended	3 Months Ended			12 Months Ended
	Jun. 30, 2011	Sep. 30, 2012	Apr. 01, 2012	Mar. 27, 2011	Mar. 31, 2013
Number of Reportable Segments					1
Proceeds from Sale of Intangible Assets		$ 500,000
Gain (Loss) on Disposition of Intangible Assets		223,000			223,000
Impairment of Intangible Assets, Finite-lived			1,700,000	7,500,000
Other Finite-Lived Intangible Assets, Gross				200,000
Proceeds from Sale of Other Assets	200,000
Write Off Of Abandoned IPR&D [Member]
Impairment of Intangible Assets, Finite-lived			300,000	800,000
Amortization of Purchased Intangible Assets [Member]
Impairment of Intangible Assets, Finite-lived			1,100,000
Amortization of Existing Technology [Member]
Impairment of Intangible Assets, Finite-lived			300,000
Write Down Of Carrying Value Of Intangible Assets [Member]
Impairment of Intangible Assets, Finite-lived				$ 6,700,000
Distributor Relationships [Member]
Finite-Lived Intangible Asset, Useful Life					6 years
Trade Names [Member]
Finite-Lived Intangible Asset, Useful Life					3 years
Minimum [Member] | Existing Technology [Member]
Finite-Lived Intangible Asset, Useful Life					2 years
Minimum [Member] | Patented Technology [Member]
Finite-Lived Intangible Asset, Useful Life					5 years
Minimum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life					6 years
Maximum [Member] | Existing Technology [Member]
Finite-Lived Intangible Asset, Useful Life					7 years
Maximum [Member] | Patented Technology [Member]
Finite-Lived Intangible Asset, Useful Life					6 years
Maximum [Member] | Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life					7 years