Commitments and Contingencies (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2025 |
Sep. 30, 2024 |
Sep. 30, 2023 |
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| Commitments and Contingencies Disclosure [Abstract] | |||
| Letters of Credit Outstanding, Amount | $ 51.1 | ||
| Special Assessment Bond | 853.4 | ||
| Land purchase contract deposits | 34.5 | $ 23.4 | |
| Purchase Obligation | $ 870.5 | ||
| Long-Term Purchase Commitment, Period | 3 years | ||
| Operating Lease, Expense | $ 4.2 | $ 3.7 | $ 3.1 |
| Lessee, Operating Lease, Liability, to be Paid, Year One | 4.1 | ||
| Lessee, Operating Lease, Liability, to be Paid, Year Two | 3.8 | ||
| Lessee, Operating Lease, Liability, to be Paid, Year Three | 3.4 | ||
| Lessee, Operating Lease, Liability, to be Paid, Year Four | 2.4 | ||
| Lessee, Operating Lease, Liability, to be Paid, Year Five | 1.6 | ||
| Lessee, Operating Lease, Liability, to be Paid, after Year Five | $ 0.4 | ||
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- References 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Amount of operating lease expense. Excludes sublease income. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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