Goodwill and Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Goodwill and Intangible Assets Disclosure [Line Items]
Impairment loss	$ 398,000	$ 1,960,000	$ 0
Amortization expense for intangible assets	10,600,000	9,800,000	6,700,000
CeligoCell Cytometer product line
Goodwill and Intangible Assets Disclosure [Line Items]
Impairment loss	$ 398,000	$ 1,960,000