v3.25.3

Revenue and Accounts Receivable - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended			42 Months Ended
	Dec. 31, 2023 USD ($)	Sep. 30, 2025 USD ($) state	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2025 USD ($) state	Nov. 30, 2023
Disaggregation of Revenue [Line Items]
Number of states excluded due to gas cost recovery mechanisms \| state		6			6
Percent of customers excluded due to gas cost recovery mechanisms		89.00%
Reduction to bad debt expense		$ (30,778)	$ (24,843)	$ (22,353)
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
Disaggregation of Revenue [Line Items]
Regulatory mechanism threshold (in percent)		75.00%

Accounts Receivable, Allowance for Credit Loss, Recovery, Uncollectible Accounts Period

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Accounts Receivable, Allowance for Credit Loss, , Uncollectible Accounts That Were Previously Written Off

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Accounts Receivable, Allowance for Credit Loss, Uncollectible Accounts That Are Not Yet Written Off

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Number of States With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms

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Percent Of Customers With Ability To Recover Uncollectible Accounts Due To Gas Cost Recovery Mechanisms

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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.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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