Other Comprehensive Income (Loss) (Tables)

9 Months Ended

Sep. 30, 2023

Stockholders' Equity Note [Abstract]

Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax

Changes in accumulated other comprehensive loss, net of tax :

	Three Months Ended Sept. 30, 2023						Three Months Ended Sept. 30, 2022
(Millions of Dollars)	Gains and Losses on Cash Flow Hedges		Defined Benefit Pension and Postretirement Items		Total		Gains and Losses on Cash Flow Hedges		Defined Benefit Pension and Postretirement Items		Total
Accumulated other comprehensive loss at July 1	$	(44)	$	(38)	$	(82)	$	(57)	$	(46)	$	(103)
Other comprehensive gain before reclassifications	3		—		3		—		10		10
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives (a)	1		—		1		1		—		1
Amortization of net actuarial loss (b)	—		—		—		—		1		1
Net current period other comprehensive income	4		—		4		1		11		12
Accumulated other comprehensive loss at Sept. 30	$	(40)	$	(38)	$	(78)	$	(56)	$	(35)	$	(91)

	Nine Months Ended Sept. 30, 2023						Nine Months Ended Sept. 30, 2022
(Millions of Dollars)	Gains and Losses on Cash Flow Hedges		Defined Benefit Pension and Postretirement Items		Total		Gains and Losses on Cash Flow Hedges		Defined Benefit Pension and Postretirement Items		Total
Accumulated other comprehensive loss at Jan. 1	$	(54)	$	(39)	$	(93)	$	(75)	$	(48)	$	(123)
Other comprehensive gain before reclassifications	11		—		11		15		11		26
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives (a)	3		—		3		4		—		4
Amortization of net actuarial loss (b)	—		1		1		—		2		2
Net current period other comprehensive income	14		1		15		19		13		32
Accumulated other comprehensive loss at Sept. 30	$	(40)	$	(38)	$	(78)	$	(56)	$	(35)	$	(91)

(a)Included in interest charges.

(b)Included in the computation of net periodic pension and postretirement benefit costs.