Capitalized Interest (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2022	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020
Capitalized Interest Costs [Line Items]
Interest Costs Incurred	$ 8.3	$ 10.3	$ 24.7	$ 33.3
Real Estate Inventory, Capitalized Interest Costs	51.7	56.5	51.7	56.5	$ 50.6	$ 53.7	$ 54.3	$ 48.7
Real Estate Inventory, Capitalized Interest Costs, Cost of Sales	$ (7.2)	$ (8.1)	$ (26.7)	$ (25.5)

[Line Items] for Capitalized Interest Costs [Table]

No definition available.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

+ 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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- Definition

Amount of interest cost charged to cost of sales that had been previously capitalized to inventory.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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