Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2021

Regulatory Assets and Liabilities Disclosure [Abstract]

Regulatory Assets

Components of regulatory assets:

(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2021				Dec. 31, 2020
Regulatory Assets			Current		Noncurrent		Current		Noncurrent
Environmental remediation costs	1, 10	Various	$	13	$	79	$	13	$	94
Pension and retiree medical obligations	9	Various	4		55		4		67
Deferred natural gas and electric energy/fuel costs	7	One to two years	2		29		—		—
State commission adjustments		Plant lives	1		21		1		20
Recoverable deferred taxes on AFUDC		Plant lives	—		19		—		18
Net AROs (a)	1, 10	Various	—		10		—		6
Losses on reacquired debt		Term of related debt	—		2		—		2
Other		Various	1		10		1		8
Total regulatory assets			$	21	$	225	$	19	$	215

(a)Includes amounts recorded for future recovery of AROs.

Regulatory Liabilities

Components of regulatory liabilities:

(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2021				Dec. 31, 2020
Regulatory Liabilities			Current		Noncurrent		Current		Noncurrent
Plant removal costs	1, 10	Various	$	—	$	201	$	—	$	184
Deferred income tax adjustments and TCJA refunds (a)	7	Various	—		152		—		161
United States Department of Energy Settlement		Various	—		14		12		—
Deferred natural gas and electric energy/fuel costs		Less than one year	3		—		17		1
Other		Various	1		5		2		4
Total regulatory liabilities			$	4	$	372	$	31	$	350

(a)    Includes the revaluation of recoverable/regulated plant accumulated deferred income taxes and revaluation impact of non-plant accumulated deferred income taxes due to the TCJA.

^[1]

[1] Includes the revaluation of recoverable/regulated plant accumulated deferred income taxes and revaluation impact of non-plant accumulated deferred income taxes due to the TCJA.