v3.8.0.1

Income Taxes - Schedule of Reconciliation Difference of Income Taxes (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015
Income Tax Disclosure [Abstract] |  |  |
Amount at statutory U.S. federal income tax rate | $ 2,461 | $ 5,932 | $ 6,385
Change because of the following items: |  |  |
State income taxes, net of federal benefit | (13) | 142 | 67
Stock-based compensation | 330 | (607) | 16
Valuation allowance change | 665 | (2,500) | 348
Tax reserve change | (52) | 258 | 34
Federal manufacturing deduction | (313) | (280) | (268)
U.S. Federal and foreign research and development credits | (706) | (571) | (74)
Gain on strategic investment and corporate subsidiary |  | 2,630 |
Foreign rate differential | 948 | 622 |
Acquisition-related transaction costs |  | 768 |
Contingent consideration (gain) expense | (45) | 522 |
Unrealized foreign currency exchange loss on contingent consideration obligation | 170 |  |
Other | (338) | 47 | (214)
Income tax provision | $ 3,107 | $ 6,963 | $ 6,294

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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