v3.8.0.1

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) |

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- Definition Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP). + References No definition available. + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318 + Details
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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 325 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031664&loc=d3e22529-158502 + Details
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