Stock-Based Compensation Status of Restricted Stock Activity and Changes (Detail) - $ / shares	9 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Shares
Awards granted (shares)	1,484,781	1,517,057
Restricted Stock, Time Based Shares [Member]
Shares
Awards granted (shares)	568,750	600,750
Board of Director Units [Member]
Shares
Awards granted (shares)	69,281	77,557
Restricted Stock, Performance Based Shares [Member]
Shares
Awards granted (shares)	846,750	838,750
Restricted stock units
Shares
Outstanding at Beginning of period (shares)	2,726,485
Awards granted (shares)	1,484,781
Awards vested (shares)	(672,453)
Awards canceled (shares)	(266,736)
Outstanding at End of period (shares)	3,272,077
Weighted Average Grant-Date Fair Value
Outstanding at beginning of period (USD per share)	$ 11.05
Awards granted (USD per share)	11.93
Awards vested (USD per share)	11.91
Awards canceled (USD per share)	10.60
Outstanding at end of period (USD per share)	$ 11.91

No definition available.

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- Definition

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

+ 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)

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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)(3)

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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

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The weighted average fair value at grant date for nonvested equity-based awards issued 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

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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-Publisher FASB

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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