v3.8.0.1

Stock-Based Compensation Plans (Tables) | 12 Months Ended
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Sep. 30, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |
Stock-Based Compensation Expenses | The Company’s stock-based compensation expenses for the years ended September 30 were allocated to the following expense categories
|  | 2017 |  |  | 2016 |  |  | 2015 |
Product costs |  | $ | 90 |  |  | $ | 22 |  |  | $ | 24 |
Research and development |  |  | 510 |  |  |  | 324 |  |  |  | 226 |
Selling, general and administrative |  |  | 2,872 |  |  |  | 3,498 |  |  |  | 2,131 |
Total stock-based compensation expense |  | $ | 3,472 |  |  | $ | 3,844 |  |  | $ | 2,381 |
Assumptions Used in Stock Option Plans | The assumptions used as inputs in the model for the years ended September 30 were as follows:
|  | 2017 |  |  | 2016 |  |  | 2015 |
Risk-free interest rates |  |  | 1.74 | % |  |  | 1.89 | % |  |  | 1.43 | %
Expected life |  | 4.6 years |  |  | 4.6 years |  |  | 4.5 years |
Expected volatility |  |  | 34 | % |  |  | 37 | % |  |  | 43 | %
Dividend yield |  |  | 0 | % |  |  | 0 | % |  |  | 0 | %
Schedule of Stock Option Activity | The following table summarizes all stock options activity and stock options outstanding and exercisable under the stock option plans during fiscal 2017, 2016 and 2015:
|  | Number of Shares |  |  | Weighted Average Exercise Price |
Outstanding at September 30, 2014 |  |  | 1,210,619 |  |  | $ | 20.35 |
Granted |  |  | 164,401 |  |  |  | 21.24 |
Exercised |  |  | (166,422 | ) |  |  | 14.54 |
Forfeited and expired |  |  | (90,590 | ) |  |  | 35.35 |
Outstanding at September 30, 2015 |  |  | 1,118,008 |  |  |  | 20.10 |
Granted |  |  | 241,582 |  |  |  | 20.63 |
Exercised |  |  | (437,850 | ) |  |  | 15.68 |
Forfeited and expired |  |  | (94,415 | ) |  |  | 31.52 |
Outstanding at September 30, 2016 |  |  | 827,325 |  |  |  | 21.30 |
Granted |  |  | 229,039 |  |  |  | 24.08 |
Exercised |  |  | (6,819 | ) |  |  | 13.89 |
Forfeited and expired |  |  | (47,640 | ) |  |  | 30.65 |
Outstanding at September 30, 2017 |  |  | 1,001,905 |  |  |  | 21.54 |
Exercisable at September 30, 2017 |  |  | 547,051 |  |  | $ | 20.80 |
Schedule of Restricted Stock Awards Activity | The following table summarizes all restricted stock awards activity during fiscal 2017, 2016 and 2015:
|  | Number of Shares |  |  | Weighted Average Grant Price |
Balance at September 30, 2014 |  |  | 18,624 |  |  | $ | 22.45 |
Granted |  |  | 18,073 |  |  |  | 21.84 |
Vested |  |  | (7,606 | ) |  |  | 22.28 |
Forfeited |  |  | (1,316 | ) |  |  | 22.16 |
Balance at September 30, 2015 |  |  | 27,775 |  |  |  | 22.12 |
Granted |  |  | 20,108 |  |  |  | 20.14 |
Vested |  |  | (12,311 | ) |  |  | 22.19 |
Forfeited |  |  | (2,439 | ) |  |  | 21.17 |
Balance at September 30, 2016 |  |  | 33,133 |  |  |  | 20.96 |
Granted |  |  | 51,559 |  |  |  | 25.12 |
Vested |  |  | (14,497 | ) |  |  | 21.10 |
Forfeited |  |  | (2,278 | ) |  |  | 25.12 |
Balance at September 30, 2017 |  |  | 67,917 |  |  | $ | 23.98 |
Schedule of Fair Value at the Date of Grant | The aggregate number of shares that could be awarded to key employees if the minimum, target and maximum performance goals are met, based upon the fair value at the date of grant is as follows:
Performance Period |  | Minimum Shares |  |  | Target Shares |  |  | Maximum Shares |
Fiscal 2015 – 2017 |  |  | 8,440 |  |  |  | 42,199 |  |  |  | 84,398 |
Fiscal 2016 – 2018 |  |  | 13,268 |  |  |  | 66,338 |  |  |  | 132,676 |
Fiscal 2017 – 2019 |  |  | 10,437 |  |  |  | 52,185 |  |  |  | 104,370 |

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- Definition Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed. + 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) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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- Definition Tabular disclosure for share-based compensation plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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 (c)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year. + 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 (c)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + 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 (f)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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