Capitalized Interest (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Statement [Line Items]
Real Estate Inventory, Capitalized Interest Costs	$ 71.9	$ 62.2	$ 71.9	$ 62.2	$ 67.7	$ 63.0	$ 60.5	$ 58.5
Interest incurred	10.6	8.2	18.8	16.3
Interest charged to cost of sales	$ (6.4)	$ (6.5)	$ (9.9)	$ (12.6)

Capitalized Interest

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
-Topic 835
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483013/835-20-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483013/835-20-50-1

+ 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/2009/role/commonPracticeRef
-Topic 835
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483013/835-20-50-1

+ Details

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- Definition

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

+ References

+ Details

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