Commitments and Contingencies (Detail) - USD ($) $ in Millions	Mar. 31, 2025	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Letters of Credit Outstanding, Amount	$ 22.3
Special Assessment Bond	804.4
Land purchase contract deposits	36.2	$ 23.4
Purchase Obligation	$ 783.7

No definition available.

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment in the future.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
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+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

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-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
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-Subparagraph (SX 210.12-04(a))
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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of a type of municipal bond typically used to fund a development project. Also called special assessment limited liability bond, special district bond, special purpose bond, special tax bond and community development obligation. Interest owed to lenders is paid by taxes levied on the community benefiting from the particular bond-funded project. For example, if a bond of this sort was issued to pay for sidewalks to be repaved in a certain community, an additional tax would be levied on homeowners in the area benefiting from this project.

+ References

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+ Details

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