Inventory Impairments and Land Option Cost Write-Offs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Inventory Impairments and Land Option Cost Write-Offs (Textuals) [Abstract]
Impairment charges			$ 37.3	$ 62.3	$ 377.8
Homebuilding [Member]
Inventory Impairments and Land Option Cost Write-Offs (Textuals) [Abstract]
Carrying value of communities with impairment indicators	391.5		391.5
Minimum range of discount rates for communities	12.00%		12.00%
Maximum range of discount rates for communities	18.00%		18.00%
Carrying value of communities impaired	37.1		37.1
Impairment charges	10.2	29.1	37.3	62.3	377.8
Percentage of impairment charges related to land inventory			78.00%	93.00%	85.00%
Percentage of impairment charges related to homes inventory			22.00%	7.00%	15.00%
Land held for sale	26.3	3.3	26.3	3.3
Write-offs (recoveries) of earnest money deposits and pre-acquisition costs			$ 8.1	$ 2.4	$ 29.9

The aggregate carrying value of communities impaired as determined through the entity's impairment analysis.

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The aggregate carrying value of communities with impairment indicators as determined through the entity's impairment analysis.

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Inventory Impairments and Land Option Cost Write-Offs.

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Of the range of discount rates used in the entity's impairment analysis, the maximum discount rate applied to communities.

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Of the range of discount rates used in the entity's impairment analysis, the minimum discount rate applied to communities.

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- Definition

The percentage of impairment charges recorded during the period that relate to construction in progress and finished homes inventory.

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The percentage of impairment charges recorded during the period that relate to residential land and lots and land held for development.

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The net write-off or recovery of earnest money deposits and pre-acquisition costs related to land option contracts during the period.

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Carrying amount as of the balance sheet date of parcels of land held for sale, and on which the entity has no intention or no further intention to perform construction activities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 3

-Section A

-Paragraph 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6386783&loc=d3e4542-108314

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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 AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 4

-Section 7

-Paragraph 14

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Concepts (CON)

-Number 6

-Paragraph 86

-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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