Consolidated Statement of Comprehensive Income (Loss) (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Other comprehensive loss:
Tax benefit from unrecognized pension and postretirement benefit plan liabilities	$ 103.1	$ 93.2	$ 71.8
Tax expense for unrealized gains and losses on cash flow hedges	$ (3.1)	$ 2.3	$ 5.0

Tax effect, net of reclassification adjustments, of the change in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Also includes an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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