Other Comprehensive Income (Loss) (Tables)

9 Months Ended

Sep. 30, 2020

Stockholders' Equity Note [Abstract]

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

Changes in accumulated other comprehensive loss, net of tax, for the three and nine months ended Sept. 30, 2020 and 2019:

	Three Months Ended Sept. 30, 2020						Three Months Ended Sept. 30, 2019
(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	$	(87)	$	(58)	$	(145)	$	(75)	$	(60)	$	(135)
Other comprehensive loss before reclassifications (net of taxes of $—, $—, $(3) and $—, respectively)	—		—		—		(9)		—		(9)
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives (net of taxes of $—) (a)	1		—		1		1		—		1
Amortization of net actuarial loss (net of taxes of $—) (b)	—		1		1		—		1		1
Net current period other comprehensive income (loss)	1		1		2		(8)		1		(7)
Accumulated other comprehensive loss at Sept. 30	$	(86)	$	(57)	$	(143)	$	(83)	$	(59)	$	(142)

	Nine Months Ended Sept. 30, 2020						Nine Months Ended Sept. 30, 2019
(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	$	(80)	$	(61)	$	(141)	$	(60)	$	(64)	$	(124)
Other comprehensive (loss) gain before reclassifications (net of taxes of $(3), $—, $(9) and $1, respectively)	(10)		—		(10)		(25)		2		(23)
Losses reclassified from net accumulated other comprehensive loss:
Interest rate derivatives (net of taxes of $1, $—, $1 and $—, respectively) (a)	4		—		4		2		—		2
Amortization of net actuarial loss (net of taxes of $—, $1, $— and $1, respectively) (b)	—		4		4		—		3		3
Net current period other comprehensive (loss) income	(6)		4		(2)		(23)		5		(18)
Accumulated other comprehensive loss at Sept. 30	$	(86)	$	(57)	$	(143)	$	(83)	$	(59)	$	(142)

(a)Included in interest charges.

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