Achievable restricted stock units maximum.

No definition available.

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- Definition

Grant date of option or restricted stock unit awards.

+ References

No definition available.

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- Definition

Grant date of fully vested restricted stock shares.

+ References

No definition available.

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- Definition

Issue date of restrict stock unit awards earned.

+ References

No definition available.

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- Definition

Number of restricted shares awarded to each director.

+ References

No definition available.

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- Definition

Weighted-average price of restricted stock units granted.

+ References

No definition available.

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- Definition

Number of common stock shares delivered as payment for the exercise price of stock options exercised.

+ References

No definition available.

+ Details

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- Definition

Tax benefit realized for tax deduction from option exercises of the share-based payment.

+ References

No definition available.

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

No definition available.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ 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 (j)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Gross value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)					3 Months Ended		9 Months Ended
	Dec. 31, 2017	May. 28, 2015	Feb. 27, 2015	May. 12, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation					$ 251,000	$ 191,000	$ 741,000	$ 525,000
Stock-based compensation cost, net of tax					160,000	$ 116,000	482,000	$ 337,000
Total intrinsic value of options exercised							$ 1,731,000
Option exercised							58,000	0
Total unrecognized compensation cost related to stock options					432,000		$ 432,000
Weighted-average period of total unrecognized compensation cost related to stock options							1 year 4 months 24 days
Stock options exercised, gross exercise value							$ 692,000
Cash received from option exercises							140,000
Tax benefit realized for tax deduction from option exercises of the share-based payment							616,000
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock delivered as payment for stock options exercised							13,000
RSUs [Member] \| 2015 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation					20,000		$ 54,000
Share based award vesting period							3 years
Grant date of award							Feb. 13, 2015
Weighted average price of restricted stock							$ 39.17
Total unrecognized compensation cost related to restricted stock units					$ 198,000		$ 198,000
Maximum number of achievable RSUs					11,000		11,000
RSUs [Member] \| 2012 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date of award							Feb. 17, 2012
Weighted average price of restricted stock							$ 18.00
RSUs earned			6,000
Issue date of earned RSUs							Feb. 27, 2015
May 12, 2014 Director Restricted Stock [Member] \| Incentive Stock Plan (2008 Plan) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date of award							May 12, 2014
Number of restricted shares awarded to each Director				3,000
Grant date of fully vested shares							May 12, 2015
May 28, 2015 Director Restricted Stock [Member] \| Incentive Stock Plan (2008 Plan) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation					$ 141,000		$ 191,000
Share based award vesting period		1 year
Grant date of award							May 28, 2015
Weighted average price of restricted stock		$ 38.00
Total unrecognized compensation cost related to restricted stock units					$ 379,000		$ 379,000
Number of restricted shares awarded to each Director		3,000
Shares granted							0
Scenario, Forecast [Member] \| RSUs [Member] \| Share-based Compensation Award, Tranche One [Member] \| 2015 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earned RSUs vesting percentage	100.00%