REGULATORY ASSETS AND LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2021

SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]

SCHEDULE OF REGULATED ASSETS AND LIABILITIES

The tables below present a summary of regulatory assets, net of amortization, and liabilities for the periods indicated:

		December 31, 2021
	Remaining Recovery Period	Current		Noncurrent		Total
		(Thousands of dollars)
Winter weather event costs	(a)	$	1,536,054	$	428,023	$	1,964,077
Under-recovered purchased-gas costs	1 year	31,863		—		31,863
Pension and other postemployment benefit costs	See Note 13	11,507		260,559		272,066
Reacquired debt costs	6 years	812		4,070		4,882
MGP remediation costs	15 years	98		29,841		29,939
Ad-valorem tax	1 year	8,561		—		8,561
WNA	1 year	10,044		—		10,044
Customer credit deferrals	1 year	10,685		—		10,685
Other	1 to 18 years	2,052		2,369		4,421
Total regulatory assets, net of amortization		1,611,676		724,862		2,336,538
Income tax rate changes	(a)	—		(552,928)		(552,928)
Over-recovered purchased-gas costs	1 year	(8,090)		—		(8,090)
Total regulatory liabilities		(8,090)		(552,928)		(561,018)
Net regulatory assets and liabilities		$	1,603,586	$	171,934	$	1,775,520

(a) Recovery period varies by jurisdiction. See discussion below for additional information regarding our regulatory assets related to winter weather event costs and regulatory liabilities related to federal income tax rate changes.

		December 31, 2020
	Remaining Recovery Period	Current		Noncurrent		Total
		(Thousands of dollars)
Under-recovered purchased-gas costs	1 year	$	16,502	$	—	$	16,502
Pension and other postemployment benefit costs	See Note 13	16,541		341,266		357,807
Reacquired debt costs	7 years	812		4,866		5,678
MGP remediation costs	15 years	98		18,711		18,809
Ad-valorem tax	1 year	5,558		—		5,558
WNA	1 year	4,806		—		4,806
Customer credit deferrals	1 year	10,267		—		10,267
Other	1 to 18 years	2,189		2,113		4,302
Total regulatory assets, net of amortization		56,773		366,956		423,729
Income tax rate changes	(a)	—		(547,563)		(547,563)
Over-recovered purchased-gas costs	1 year	(15,761)		—		(15,761)
Total regulatory liabilities		(15,761)		(547,563)		(563,324)
Net regulatory assets and liabilities		$	41,012	$	(180,607)	$	(139,595)