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Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Income Taxes [Line Items] |  |  |  |
Effective tax rate (ETR) from continuing operations | (1.20%) | 3.90% | 3.70% | (0.20%)
State net operating loss carryforwards | $ 0 |  | $ 0 |
Domestic Tax Authority [Member] | 2030-2038 [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Net operating loss carryforwards | 277,600,000 |  | 277,600,000 |
State and Local Jurisdiction [Member] | 2024-2043 [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Net operating loss carryforwards | $ 150,600,000 |  | $ 150,600,000 |
Minimum [Member] | Domestic Tax Authority [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards, expiration year |  |  | 2030 |
Minimum [Member] | State and Local Jurisdiction [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards, expiration year |  |  | 2024 |
Maximum [Member] | Domestic Tax Authority [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards, expiration year |  |  | 2038 |
Maximum [Member] | State and Local Jurisdiction [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Operating loss carryforwards, expiration year |  |  | 2043 |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 + Details
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