Postretirement Benefits - Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Compensation and Retirement Disclosure [Abstract]
Net loss (gain)	$ 961	$ (791)
Amortization of net loss	(2)	(3)
Curtailment loss	0	(675)
Settlement loss	0	(87)
Total recognized in other comprehensive income (loss)	959	(1,556)
Total recognized in net periodic pension cost and other comprehensive income (loss)	$ 1,307	$ (887)

Defined Benefit Plan, Accumulated Other Comprehensive Income Amortization Of Net Gains (Losses), After Tax

No definition available.

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- Definition

Defined Benefit Plan, Accumulated Other Comprehensive Income Curtailment Gain (Loss), After Tax

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Accumulated Other Comprehensive Income Settlement Gain (Loss), After Tax

+ References

No definition available.

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- Definition

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (j-k)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount recognized in net periodic benefit cost and other comprehensive income.

+ References

No definition available.

+ Details

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- Definition

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

+ Details

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