Regulation (Tables)

9 Months Ended

Jun. 30, 2024

Regulated Operations [Abstract]

Schedule of Regulatory Assets

Regulatory assets and liabilities as of June 30, 2024 and September 30, 2023 included the following:

	June 30, 2024		September 30, 2023
	(In thousands)
Regulatory assets:
Pension and postretirement benefit costs	$	14,033	$	20,629
Infrastructure mechanisms (1)	209,609		229,996
Winter Storm Uri incremental costs	12,549		32,115
Deferred gas costs	68,296		148,297
Regulatory excess deferred taxes (2)	50,462		47,549
Recoverable loss on reacquired debt	3,112		3,238
Deferred pipeline record collection costs	42,454		54,008
APT annual System Safety and Integrity Rider	35,721		—
Other	15,288		19,096
	$	451,524	$	554,928
Regulatory liabilities:
Regulatory excess deferred taxes (2)	$	283,073	$	384,513
Regulatory cost of removal obligation	605,449		582,867
Deferred gas costs	20,188		23,093
APT annual adjustment mechanism	48,544		49,894
Pension and postretirement benefit costs	199,838		215,913
Other	30,280		28,054
	$	1,187,372	$	1,284,334

(1)Infrastructure mechanisms in Texas, Louisiana and Tennessee allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates.

(2)Regulatory excess deferred taxes represent changes in our net deferred tax liability related to our cost of service ratemaking due to the enactment of Tax Cuts and Jobs Act of 2017 (the "TCJA") and a Kansas legislative change enacted in fiscal 2020. See Note 12 to the condensed consolidated financial statements for further information.

Schedule of Regulatory Liabilities

Regulatory assets and liabilities as of June 30, 2024 and September 30, 2023 included the following:

	June 30, 2024		September 30, 2023
	(In thousands)
Regulatory assets:
Pension and postretirement benefit costs	$	14,033	$	20,629
Infrastructure mechanisms (1)	209,609		229,996
Winter Storm Uri incremental costs	12,549		32,115
Deferred gas costs	68,296		148,297
Regulatory excess deferred taxes (2)	50,462		47,549
Recoverable loss on reacquired debt	3,112		3,238
Deferred pipeline record collection costs	42,454		54,008
APT annual System Safety and Integrity Rider	35,721		—
Other	15,288		19,096
	$	451,524	$	554,928
Regulatory liabilities:
Regulatory excess deferred taxes (2)	$	283,073	$	384,513
Regulatory cost of removal obligation	605,449		582,867
Deferred gas costs	20,188		23,093
APT annual adjustment mechanism	48,544		49,894
Pension and postretirement benefit costs	199,838		215,913
Other	30,280		28,054
	$	1,187,372	$	1,284,334

(1)Infrastructure mechanisms in Texas, Louisiana and Tennessee allow for the deferral of all eligible expenses associated with capital expenditures incurred pursuant to these rules, including the recording of interest on deferred expenses until the next rate proceeding (rate case or annual rate filing), at which time investment and costs would be recoverable through base rates.

(2)Regulatory excess deferred taxes represent changes in our net deferred tax liability related to our cost of service ratemaking due to the enactment of Tax Cuts and Jobs Act of 2017 (the "TCJA") and a Kansas legislative change enacted in fiscal 2020. See Note 12 to the condensed consolidated financial statements for further information.