Basis of Presentation and Significant Accounting Policies - Summary of Status of Company's Non-Vested Shares (Detail) (USD $)	3 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Outstanding Beginning Balance	1,240,941
Shares, Granted	291,654
Options, Forfeited	(27,833)
Options, Outstanding Ending Balance	1,504,762
Weighted-Average Grant Date Fair Value, Granted	$ 3.23
Non-Vested Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Outstanding Beginning Balance	539,519
Shares, Granted	291,654
Shares, Vested	(202,125)
Options, Forfeited	(5,718)
Options, Outstanding Ending Balance	623,330
Weighted-Average Grant Date Fair Value, Non-vested Beginning Balance	$ 3.29
Weighted-Average Grant Date Fair Value, Granted	$ 3.23
Weighted-Average Grant Date Fair Value, Vested	$ 3.05
Weighted-Average Grant Date Fair Value, Forfeited	$ 3.41
Weighted-Average Grant Date Fair Value, Non-vested Ending Balance	$ 3.34

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ 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)(iv)(3)

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

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)

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

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

+ References

No definition available.

+ Details

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&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 (c)(1)(i)-(ii)

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

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- Definition

Number of options vested.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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