Summary of Significant Accounting Policies (Details) (Homebuilding [Member], USD $) In Millions	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Homebuilding [Member]
Rollforward of capitalized homebuilding interest
Capitalized interest, beginning of year	$ 91.5	$ 128.8	$ 160.6
Interest incurred	130.2	173.2	205.0
Interest expensed:
Directly to interest expense	(50.5)	(86.3)	(100.2)
Amortized to cost of sales	(90.8)	(122.1)	(122.8)
Written off with inventory impairments	(1.2)	(2.1)	(13.8)
Capitalized interest, end of year	$ 79.2	$ 91.5	$ 128.8

The amount of interest costs that had been capitalized to inventory which were written off with inventory impairments during the period.

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- Definition

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

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Section 50

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- Definition

The cost of borrowed funds accounted for as interest that was charged against earnings during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

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-Section S99

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-Subparagraph (SX 210.9-04.9)

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-Number 34

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

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-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 9

-Subsection II

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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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 Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 34

-Paragraph 9, 11, 12, 13, 14, 15, 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

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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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