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v3.25.3

Summary of Significant Accounting Policies - Narrative (Details) |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Nov. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) | Sep. 30, 2025 USD ($) plan mi | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($)
Alternative Revenue Program [Line Items] |  |  |  |  |
Number of asset management plans under management | plan |  |  | 2 |  |
Composite depreciation rate for regulated property, plant and equipment |  |  | 2.80% | 2.90% | 3.00%
Impairment of long-lived assets |  |  | $ 0 | $ 0 | $ 0
Derivative, cash collateral |  |  | 0 | $ 0 |
Self-insured retention |  |  | $ 1,000,000 |  |
Pipeline and Storage |  |  |  |  |
Alternative Revenue Program [Line Items] |  |  |  |  |
Regulatory mechanism threshold (in percent) |  |  | 75.00% |  |
Rate case revenue benchmark | $ 69,400,000 | $ 106,900,000 |  |  |
Pipeline and Storage | State of Louisiana |  |  |  |  |
Alternative Revenue Program [Line Items] |  |  |  |  |
Length of pipeline | mi |  |  | 21 |  |

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- Definition Amount of cash pledged as collateral against derivative liabilities. + References No definition available. + Details
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- Definition Number of Asset Management Plans Under Management + References No definition available. + Details
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- Definition Rate case revenue benchmark as set in the APT rate case filing and part of our regulatory mechanism. This revenue benchmark is used in calculating the total revenue to be billed or returned to customers. + References No definition available. + Details
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- Definition APT has a regulatory mechanism that requires that we share with its tariffed customers a set percentage, as determined through the rate case filings, of the difference between the total non-tariffed revenues earned during a test period and a revenue benchmark. + References No definition available. + Details
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-11 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 100 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-100 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-2 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482130/360-10-45-4 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 21 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-21 + Details
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