Changes in Accumulated Other Comprehensive Loss (Tables)

3 Months Ended

Mar. 31, 2021

Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]

Schedule of changes in accumulated other comprehensive loss including reclassification adjustments, net of tax, by component

The following table shows the changes in Pinnacle West’s consolidated accumulated other comprehensive loss, including reclassification adjustments, net of tax, by component (dollars in thousands):

	Pension and Other Postretirement Benefits			Derivative Instruments			Total
Three Months Ended March 31
Balance December 31, 2020	$	(60,725)		$	(2,071)		$	(62,796)
OCI (loss) before reclassifications	—			262			262
Amounts reclassified from accumulated other comprehensive loss	1,022		(a)	—			1,022
Balance March 31, 2021	$	(59,703)		$	(1,809)		$	(61,512)
Balance December 31, 2019	$	(56,522)		$	(574)		$	(57,096)
OCI (loss) before reclassifications	—			292			292
Amounts reclassified from accumulated other comprehensive loss	1,205		(a)	20		(b)	1,225
Balance March 31, 2020	$	(55,317)		$	(262)		$	(55,579)

(a)    These amounts primarily represent amortization of actuarial loss and are included in the computation of net periodic pension cost.  See Note 5.

(b)    These amounts primarily represent realized gains and losses and are included in the computation of fuel and purchased power costs and are subject to the PSA.  See Note 7.

The following table shows the changes in APS’s consolidated accumulated other comprehensive loss, including reclassification adjustments, net of tax, by component for the three months ended March 31, 2021 and 2020 (dollars in thousands): 

	Pension and Other Postretirement Benefits			Derivative Instruments			Total
Three Months Ended March 31
Balance December 31, 2020	$	(40,918)		$	—		$	(40,918)
Amounts reclassified from accumulated other comprehensive loss	927		(a)	—			927
Balance March 31, 2021	$	(39,991)		$	—		$	(39,991)
Balance December 31, 2019	$	(34,948)		$	(574)		$	(35,522)
OCI (loss) before reclassifications	—			292			292
Amounts reclassified from accumulated other comprehensive loss	1,013		(a)	20		(b)	1,033
Balance March 31, 2020	$	(33,935)		$	(262)		$	(34,197)

(a) These amounts primarily represent amortization of actuarial loss and are included in the computation of net periodic pension cost.  See Note 5.

(b) These amounts primarily represent realized gains and losses and are included in the computation of fuel and purchased power costs and are subject to the PSA.  See Note 7.