| **Palo Verde Leaseback Variable Interest Entities - Schedule of VIEs (Details) - USD ($) $ in Thousands** | Dec. 31, 2019 | Dec. 31, 2018 |
|-----------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets**                        |          |          |
| Palo Verde sale leaseback, net of accumulated depreciation                                                | $ 101,906     | $ 105,775     |
| Equity - noncontrolling interests                                                                         | 122,540       | 125,790       |
| ARIZONA PUBLIC SERVICE COMPANY                                                                            |          |          |
| **Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets**                        |          |          |
| Palo Verde sale leaseback, net of accumulated depreciation                                                | 101,906       | 105,775       |
| Equity - noncontrolling interests                                                                         | 122,540       | 125,790       |
| ARIZONA PUBLIC SERVICE COMPANY | Consolidation of VIEs                                                    |          |          |
| **Amounts relating to the VIEs included in Condensed Consolidated Balance Sheets**                        |          |          |
| Palo Verde sale leaseback, net of accumulated depreciation                                                | 101,906       | 105,775       |
| Equity - noncontrolling interests                                                                         | $ 122,540     | $ 125,790     |

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| - Definition
Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).
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| - Definition
The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.
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