Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Line Items]
U.S. federal statutory tax rate	35.00%	35.00%	35.00%
Increase (Decrease) in deferred tax assets	$ 665,000	$ (2,500,000)	$ 348,000
Excess tax benefits (shortfalls) related to stock based compensation expense	(200,000)	600,000
Excess tax benefit from stock-based compensation plans			432,000
Deferred tax asset valuation allowance	$ 4,511,000	3,847,000
Net operating loss carryforwards, remaining period	10 years
Unrecognized tax benefits excluding interest and penalties that would impact effective tax rate	$ 1,200,000	1,200,000	900,000
Liability for unrecognized tax benefits to change significantly in the next 12 months	500,000	600,000	$ 600,000
Undistributed earnings in foreign subsidiaries	0	0
State [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 200,000
Net operating loss carryforwards, begening of expiration year	2022
Ireland and Luxembourg [Member] | Creagh Medical Ltd [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 3,000,000
R&D Credit Carryforwards [Member] | Federal and Minnesota [Member]
Income Tax Disclosure [Line Items]
Tax credit carryforwards	$ 300,000
Tax credit carryforward, begening of expiration year	2029
In Vitro Diagnostics [Member]
Income Tax Disclosure [Line Items]
Capital losses generated		7,500,000
Increase (Decrease) in deferred tax assets		$ (2,600,000)