Extended vesting period after employee termination.

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- Definition

Number of awards.

+ References

No definition available.

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- Definition

Number of cash settled restricted stock units outstanding.

+ References

No definition available.

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Number of cash settled restricted stock units settled.

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No definition available.

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- Definition

Reduction in shares available for grant for one award under share based compensation plan.

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No definition available.

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- Definition

Restricted stock share based compensation arrangement by share based payment award award vesting period.

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No definition available.

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- Definition

Restricted Stock Units Vesting Percentage

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- Definition

Share based compensation arrangement by share based payment award additional shares available for grant as result of amendment.

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, award cliff vesting period.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment number of awards.

+ References

No definition available.

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- Definition

Share-based compensation, other than options grants in the period, grant date fair value.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (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.

+ References

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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

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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=66902209&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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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 difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ 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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- 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

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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

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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)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ References

No definition available.

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Share-Based Compensation - Additional Information (Detail) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($) award shares	Sep. 30, 2015 USD ($) shares	Jun. 30, 2014 shares	Dec. 09, 2015 shares	Dec. 04, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation \| $	$ 10,160	$ 8,392
Total income tax benefit recognized \| $	$ 2,300	$ 2,000
Number of stock options, granted	0	0
Total intrinsic value of options exercised \| $	$ 1,100	$ 2,300
Extended vesting period after employee termination, days	90 days
Cliff vesting period, in years	3 years	3 years	3 years
Restricted Stock Units with Earning Per Share Performance Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	210,476	174,676	130,616
Restricted stock units, grant date fair value			100.00%
Restricted Stock Units with Market Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	210,476	174,676	130,641
Restricted stock units, grant date fair value			78.00%
Monte Carlo Simulation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, grant date fair value \| $	$ 11,400	$ 12,300
Cash-Settled Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	1,853
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $	$ 158,500
Aggregate intrinsic value of equity classified restricted stock \| $	$ 111,500
Weighted average recognition period, years	2 years 3 months 18 days
2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Option and Incentive Plan, maturity date	Dec. 07, 2021
Additional shares available for grant				2,000,000	2,869,821
Reduction in shares available for grant for one award under the plan	100.00%
Number of awards \| award	2
Awards vesting period	3 years	3 years
Shares available for grant	3,838,141
Number of cash-settled restricted stock units settled	2,268	869
Number of cash-settled restricted stock units, outstanding	10,260
2012 Plan [Member] \| Time Vested Restricted Stock Units Cliff Vest [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	6,830	5,243
Restricted stock units vesting period	3 years	3 years
2012 Plan [Member] \| Time Vested Restricted Stock Units Ratably Vest [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	484,174	324,987
Restricted stock units vesting period	3 years	3 years
2012 Plan [Member] \| Time Vested Restricted Stock Units Cliff Vest One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	0	294
Restricted stock units vesting period	1 year	1 year
2012 Plan [Member] \| Full-Value Grant [Member] \| Prior to December 4, 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in shares available for grant for one award under the plan	171.00%
2012 Plan [Member] \| Full-Value Grant [Member] \| On or After December 4, 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in shares available for grant for one award under the plan	150.00%
2012 Plan [Member] \| Option or Stock Appreciation Right Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards for reduction of shares available for grant under 2012 Plan \| award	1
2012 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of our common stock under 2012 Plan				9,269,821	7,269,821
2012 Plan [Member] \| Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards expiration period	10 years
2012 Plan [Member] \| Options to Purchase Common Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	5 years
2012 Plan [Member] \| Options to Purchase Common Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	3 years
2012 Plan [Member] \| Stock-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	911,956
2012 Plan [Member] \| Cash-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	6,136	4,923
2012 Plan [Member] \| Cash-Settled Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted	1,853