Summary of Changes in the Fair Value of The Company's Level 3 Pension Plan Assets (Detail) (Unobservable Inputs (Level 3), Insurance contracts, USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Unobservable Inputs (Level 3) \| Insurance contracts
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of period	$ 0	$ 4.4
Realized gain on plan assets	0	0.3
Unrealized gain on plan assets	0	0
Foreign currency translation	0	0
Purchases, sales, issuances and settlements (net)	0	(4.7)
Fair value of plan asset at end of period	$ 0	$ 0

Amount of increase or decreas in plan assets from realized gain (loss) in plan asset values.

No definition available.

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- Definition

Amount of increase or decrease in plan assets from unrealized gain (loss) in plan asset values.

+ References

No definition available.

+ Details

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- Details

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930

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- Definition

The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

+ Details

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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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