Operating Segments - Segment Revenue, Operating Income and Depreciation and Amortization (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Total revenue	$ 15,336	$ 14,616	$ 13,604	$ 13,883	$ 14,297	$ 14,289	$ 13,695	$ 13,851	$ 57,439	$ 56,132	$ 51,928
Operating income	5,434	5,333	3,480	4,329	5,576	4,238	4,129	4,877	18,576	18,820	16,342
Depreciation and amortization									2,715	2,886	2,929
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income									26,095	25,386	22,973
Operating Segments [Member] | Medical Device [Member]
Segment Reporting Information [Line Items]
Total revenue									43,068	41,153	37,883
Operating income									22,636	21,164	18,431
Depreciation and amortization									1,136	1,255	1,414
Operating Segments [Member] | In Vitro Diagnostics [Member]
Segment Reporting Information [Line Items]
Total revenue									14,371	14,979	14,045
Operating income									3,459	4,222	4,542
Depreciation and amortization									850	864	774
Corporate [Member]
Segment Reporting Information [Line Items]
Operating income									(7,519)	(6,566)	(6,631)
Depreciation and amortization									$ 729	$ 767	$ 741