Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Line Items]
U.S. federal statutory tax rate		35.00%	35.00%	35.00%
Reduction in deferred tax assets and valuation allowances		$ (2,500,000)	$ 348,000	$ 120,000
Income tax benefit from discontinued operations				100,000
Income tax expense		6,963,000	6,294,000	6,265,000
Excess tax benefit from stock-based compensation plans			432,000	236,000
Deferred tax asset valuation allowance	$ 3,847,000	3,847,000	5,721,000
Unrecognized tax benefits excluding interest and penalties that would impact effective tax rate	1,200,000	1,200,000	900,000	1,000,000
Liability for unrecognized tax benefits to change significantly in the next 12 months	600,000	600,000	600,000	$ 700,000
Undistributed earnings in foreign subsidiaries	0	0	$ 0
Accounting Standards Update 2016 09 [Member]
Income Tax Disclosure [Line Items]
Income tax expense	$ 500,000
Accounting Standards Update 2016 09 [Member] | Restatement Adjustment [Member]
Income Tax Disclosure [Line Items]
Income tax expense		600,000
In Vitro Diagnostics [Member]
Income Tax Disclosure [Line Items]
Capital losses realized		7,500,000
Reduction in deferred tax assets and valuation allowances		$ 2,600,000