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Revenue and Accounts Receivable - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 36 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2025 | Nov. 30, 2023
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |
Percent of customers excluded |  |  |  | 89.00% |  |  |
Reduction to bad debt expense | $ (14,391) | $ (12,797) |  | $ (23,015) | $ (19,547) |  |
Recovery of uncollectible accounts, not yet been written off |  |  |  |  | $ 4,192 |  |
Mississippi Public Service Commission |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |
Recovery of uncollectible accounts, term |  |  | 2 years |  |  |  | 1 year
Reduction to bad debt expense |  |  | $ 13,900 |  |  |  |
Recovery of uncollectible accounts, previously written off but not yet recovered through rates |  |  |  |  |  | $ 9,700 |
Recovery of uncollectible accounts, not yet been written off |  |  | $ 4,200 |  |  |  |
Pipeline and storage segment |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |
Regulatory mechanism threshold |  |  |  | 75.00% |  |  |

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- Definition Percent of Customers Whose Gas Cost Portion Of Bill Is Excluded From Allowance For Uncollectable Account + 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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