Capitalized Interest (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Rollforward of capitalized interest
Capitalized interest, beginning of period	$ 103.8	$ 81.1	$ 82.3	$ 79.2
Interest incurred	44.4	31.8	125.5	89.6
Interest expensed:
Directly to interest expense	0	6.9	7.1	21.1
Amortized to cost of sales	(28.6)	(24.8)	(81.1)	(66.5)
Capitalized interest, end of period	119.6	81.2	119.6	81.2
Financial Services [Member]
Rollforward of capitalized interest
Interest incurred	$ 1.4	$ 0.6	$ 3.4	$ 2.4

Total interest costs incurred during the period and either capitalized or charged against earnings.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

+ Details

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- Details

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- Definition

Carrying amount as of the balance sheet date of interest costs that were capitalized to properties under development during the land development and construction period of a project, and which are included in inventory.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

+ Details

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- Definition

The amount of interest costs that had been capitalized to inventory which were charged to cost of sales during the period.

+ References

+ Details

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- Details

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