Unrecognized cost of unvested share-based compensation awards.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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

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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.

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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

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

Number of share instruments newly issued under a share-based compensation 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

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

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Stock-Based Compensation - Additional Information (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Millions		9 Months Ended	12 Months Ended
	Nov. 21, 2013	Jun. 30, 2015	Sep. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense		$ 10.4
Expected period for recognition of unrecognized compensation expense		2 years 6 months
1997 Key Employee Stock Option Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted shares issued	184,000
Fair value of the Company’s common stock on the date of grant	$ 98.68
Unrecognized compensation expense	$ 17.3
Expected period for recognition of unrecognized compensation expense	4 years
2014 Long Term Incentive Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted shares issued		3,000	13,000
Fair value of the Company’s common stock on the date of grant		$ 19.13	$ 45.68