Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2022

Regulatory Assets and Liabilities Disclosure [Abstract]

Components of regulatory assets:


(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2022				Dec. 31, 2021 (a)
Regulatory Assets			Current		Noncurrent		Current		Noncurrent
Environmental remediation costs	1, 10	Various	$	13	$	63	$	13	$	79
Pension and retiree medical obligations	9	Various	2		61		4		55
State commission adjustments		Plant lives	1		22		1		21
Recoverable deferred taxes on AFUDC		Plant lives	—		20		—		19
Net AROs (b)	1, 10	Various	—		18		—		10
Deferred natural gas and electric energy/fuel costs	7	One year	23		—		2		29
Other		Various	5		9		1		12
Total regulatory assets			$	44	$	193	$	21	$	225

(a)Prior period amounts have been restated to conform with current year presentation.

(b)Includes amounts recorded for future recovery of AROs, less amounts recovered through NSP-Wisconsin’s share of nuclear decommissioning accruals and gains from decommissioning investments.

Regulatory Liabilities

Components of regulatory liabilities:


(Millions of Dollars)	See Note(s)	Remaining Amortization Period	Dec. 31, 2022				Dec. 31, 2021
Regulatory Liabilities			Current		Noncurrent		Current		Noncurrent
Plant removal costs	1, 10	Various	$	—	$	223	$	—	$	201
Deferred income tax adjustments and TCJA refunds (a)	7	Various	—		144		—		152
United States Department of Energy Settlement		Various	12		3		—		14
Deferred natural gas and electric energy/fuel costs		Less than one year	5		—		3		—
Other		Various	4		13		1		5
Total regulatory liabilities			$	21	$	383	$	4	$	372

(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.