Other Assets - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2015	Sep. 30, 2006
CeloNova BioSciences, Inc. [Member] | Maximum [Member]
Schedule of Investments [Line Items]
Company's ownership percentage		2.00%
ViaCyte, Inc. [Member]
Schedule of Investments [Line Items]
Impairment loss on investment	$ 0.1	$ 5.3	$ 4.7
Cost method of investment		$ 0.5
ViaCyte, Inc. [Member] | Maximum [Member]
Schedule of Investments [Line Items]
Company's ownership percentage		1.00%