Capitalized Interest (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Statement [Line Items]
Real Estate Inventory, Capitalized Interest Costs	$ 58.8	$ 50.6	$ 58.8	$ 50.6	$ 55.7	$ 52.5	$ 52.9	$ 53.7
Interest incurred	8.2	8.1	16.4	16.3
Interest charged to cost of sales	$ (5.1)	$ (10.4)	$ (10.1)	$ (19.4)

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

+ 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
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 20
-Topic 835
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483013/835-20-50-1

+ Details

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