Fair Value Measurements (Details) (USD $) In Millions	Jun. 30, 2011	Sep. 30, 2010
Fair value balance sheet items measured on a recurring basis
Marketable securities, available-for-sale	$ 297.1	$ 297.7
Mortgage loans held for sale	286.2	253.8
Homebuilding [Member]
Fair value balance sheet items measured on a recurring basis
Marketable securities, available-for-sale	297.1	297.7
Homebuilding [Member] \| Level 1 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Marketable securities, available-for-sale	9.1	1.0
Homebuilding [Member] \| Level 2 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Marketable securities, available-for-sale	288.0	296.7
Homebuilding [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Marketable securities, available-for-sale	297.1	297.7
Financial Services [Member]
Fair value balance sheet items measured on a recurring basis
Mortgage loans held for sale	286.2	253.8
Financial Services [Member] \| Interest Rate Lock Commitments [Member] \| Level 1 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	0	0
Financial Services [Member] \| Interest Rate Lock Commitments [Member] \| Level 2 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	0.3	1.8
Financial Services [Member] \| Interest Rate Lock Commitments [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	0.3	1.8
Financial Services [Member] \| Best-Efforts Delivery Commitments [Member] \| Level 1 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	0	0
Financial Services [Member] \| Best-Efforts Delivery Commitments [Member] \| Level 2 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	1.5	0.2
Financial Services [Member] \| Best-Efforts Delivery Commitments [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	1.5	0.2
Financial Services [Member] \| Hedging Instruments Related to IRLCs [Member] \| Level 1 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	0	0
Financial Services [Member] \| Hedging Instruments Related to IRLCs [Member] \| Level 2 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	(0.1)	(1.8)
Financial Services [Member] \| Hedging Instruments Related to IRLCs [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Fair value of interest rate derivatives	(0.1)	(1.8)
Financial Services [Member] \| Level 1 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Mortgage loans held for sale	0	0
Financial Services [Member] \| Level 2 [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Mortgage loans held for sale	286.2	253.8
Financial Services [Member] \| Fair Value Measurements, Recurring [Member]
Fair value balance sheet items measured on a recurring basis
Mortgage loans held for sale	$ 286.2	$ 253.8

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 12
-Subparagraph b
-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 FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 15D
-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 FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
-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 FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 15C
-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 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13
-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 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (b)-(g)
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 137
-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 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
-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 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558

+ Details

- Definition

Carrying amount of mortgage loans to individuals not classified as held for investment but are held-for-sale.

+ References+ Details