Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	$ 4,719,457	$ 4,519,102	$ 4,340,460
Total other comprehensive income	926	23,393	9,912
Ending balance	4,935,912	4,719,457	4,519,102
Derivative Instruments
Changes in accumulated other comprehensive income (loss) by component
OCI (loss) before reclassifications	(538)	(957)
Amounts reclassified from accumulated other comprehensive loss	2,941	4,187
Total other comprehensive income	2,403	3,230
Pension and Other Postretirement Benefits
Changes in accumulated other comprehensive income (loss) by component
OCI (loss) before reclassifications	(4,509)	16,980
Amounts reclassified from accumulated other comprehensive loss	3,032	3,183
Total other comprehensive income	(1,477)	20,163
AOCI Including Portion Attributable to Noncontrolling Interest
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	(44,748)	(68,141)
Ending balance	(43,822)	(44,748)	(68,141)
ARIZONA PUBLIC SERVICE COMPANY
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	4,814,794	4,629,852	4,454,874
Total other comprehensive income	1,674	21,236	5,039
Ending balance	5,037,970	4,814,794	4,629,852
ARIZONA PUBLIC SERVICE COMPANY \| Derivative Instruments
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	(27,097)	(48,333)
Ending balance	(25,423)	(27,097)	$ (48,333)
ARIZONA PUBLIC SERVICE COMPANY \| Pension and Other Postretirement Benefits
Changes in accumulated other comprehensive income (loss) by component
OCI (loss) before reclassifications	(538)	(957)
Amounts reclassified from accumulated other comprehensive loss	2,941	4,187
Total other comprehensive income	2,403	3,230
ARIZONA PUBLIC SERVICE COMPANY \| AOCI Including Portion Attributable to Noncontrolling Interest
Changes in accumulated other comprehensive income (loss) by component
OCI (loss) before reclassifications	(3,821)	14,726
Amounts reclassified from accumulated other comprehensive loss	3,092	3,280
Total other comprehensive income	$ (729)	$ 18,006

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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