Other Assets - Additional Information (Detail) (USD $)	6 Months Ended		3 Months Ended		6 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2013 Maximum [Member]	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 CeloNova BioSciences, Inc. [Member] Maximum [Member]	Mar. 31, 2014 Vessix Vascular, Inc. [Member]	Mar. 31, 2014 ThermopeutiX, Inc. [Member] Maximum [Member]	Mar. 31, 2013 ViaCyte, Inc. [Member]	Mar. 31, 2014 ViaCyte, Inc. [Member]	Sep. 30, 2006 ViaCyte, Inc. [Member]	Mar. 31, 2014 ViaCyte, Inc. [Member] Maximum [Member]	Dec. 31, 2013 Investment In Vessix Vascular, Inc. [Member]	Mar. 31, 2014 Investment In Vessix Vascular, Inc. [Member]	Sep. 30, 2010 Investment In Vessix Vascular, Inc. [Member]	Mar. 31, 2014 Investment In Vessix Vascular, Inc. [Member] Clinical milestone [Member]	Mar. 31, 2014 Investment In Vessix Vascular, Inc. [Member] Sales milestone [Member]	Mar. 31, 2014 Investment In Vessix Vascular, Inc. [Member] Maximum [Member]
Schedule of Investments [Line Items]
Company's ownership percentage						2.00%		20.00%				1.00%
Impairment loss on investment							$ 1,200,000		$ 100,000	$ 5,300,000	$ 4,700,000			$ 2,500,000	$ 2,400,000
Cost method of investment										500,000
Gain on sale of investment	806,000	1,458,000											1,200,000
Milestone payment to be received																700,000	100,000
Potential proceeds on achievement of future milestones																		3,400,000
Revenue recognized from activity with companies in which it had strategic investment		$ 100,000	$ 100,000	$ 100,000	$ 100,000