Other License Agreements and Acquired Product Rights - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	1 Months Ended	3 Months Ended
	Oct. 07, 2010	Nov. 30, 2011	Mar. 31, 2014	Sep. 30, 2013
Kunwha License Agreement [Member]
Other License Agreements And Acquired Product Rights [Line Items]
Expiration date of the agreement			Jul. 23, 2027
Upfront payment			$ 0.3
Up-front payment net of tax			0.25
Milestone payments			1.3
Milestone payments net of tax			1.1
TTY License and Supply Agreement [Member]
Other License Agreements And Acquired Product Rights [Line Items]
Upfront payment	0.3
Milestone payments	1.3
Term of the agreement			15 years
Milestone payment received		$ 0.3		$ 0.3