XML 72 R60.htm IDEA: XBRL DOCUMENT v3.23.1
Commitments and Contingencies (Details)
$ in Millions
3 Months Ended 12 Months Ended 120 Months Ended
Sep. 30, 2022
USD ($)
Nov. 02, 2021
USD ($)
Nov. 01, 2021
USD ($)
Jul. 03, 2018
USD ($)
Apr. 05, 2018
plaintiff
defendant
Dec. 16, 2016
plaintiff
Jul. 06, 2016
Aug. 06, 2013
defendant
Mar. 31, 2023
USD ($)
Trust
MW
Dec. 31, 2022
USD ($)
Jun. 30, 2021
USD ($)
claim
Apr. 18, 2023
USD ($)
Commitments and Contingencies                        
Increase in contractual obligations                 $ 1,900.0      
Production tax credit guarantees                 33.0      
Subsequent Event                        
Commitments and Contingencies                        
Non recourse construction financing agreement                       $ 140.0
Financing agreement of sponsor equity                       $ 40.0
Purchase Power Lease Contracts                        
Commitments and Contingencies                        
Increase in contractual obligations                 $ 1,600.0      
Kūpono Solar                        
Commitments and Contingencies                        
Project plant capacity (in MW's) | MW                 42      
Asset purchase agreement                 20 years      
APS                        
Commitments and Contingencies                        
Maximum insurance against public liability per occurrence for a nuclear incident (up to)                 $ 13,700.0      
Maximum available nuclear liability insurance (up to)                 450.0      
Remaining nuclear liability insurance through mandatory industry wide retrospective assessment program                 13,200.0      
Maximum retrospective premium assessment per reactor for each nuclear liability incident                 137.6      
Annual limit per incident with respect to maximum retrospective premium assessment                 $ 20.5      
Number of VIE lessor trusts | Trust                 3      
Maximum potential retrospective assessment per incident of APS                 $ 120.1      
Annual payment limitation with respect to maximum potential retrospective premium assessment                 17.9      
Amount of "all risk" (including nuclear hazards) insurance for property damage to, and decontamination of, property at Palo Verde                 2,800.0      
Maximum amount that could be incurred under retrospective assessment of NEIL policies                 22.4      
Collateral assurance provided based on rating triggers                 $ 62.6      
Period to provide collateral assurance based on rating triggers                 20 days      
APS | Contaminated groundwater wells                        
Commitments and Contingencies                        
Costs related to investigation and study under Superfund site                 $ 3.0      
Number of defendants against whom Roosevelt Irrigation District (RID) filed lawsuit | defendant         28     24        
Number of plaintiffs | plaintiff           2            
Costs claimed                   $ 21.0    
APS | Contaminated groundwater wells | Settled Litigation                        
Commitments and Contingencies                        
Number of plaintiffs | plaintiff         2              
APS | Contaminated groundwater wells | Pending Litigation                        
Commitments and Contingencies                        
Settlement amount $ 20.7                      
APS | Letter of Credit                        
Commitments and Contingencies                        
Outstanding letters of credit                 10.0      
APS | Surety Bonds Expiring in 2025                        
Commitments and Contingencies                        
Surety bonds expiring, amount                 21.0      
APS | Coal Combustion Waste | Four Corners                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 30.0      
APS | Coal Combustion Waste | Four Corners | Minimum                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 10.0      
APS | Coal Combustion Waste | Four Corners | Maximum                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 15.0      
APS | Coal Combustion Waste | Cholla                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 16.0      
APS | Coal Combustion Waste | Cholla | Minimum                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 30.0      
APS | Coal Combustion Waste | Cholla | Maximum                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 35.0      
APS | Coal Combustion Waste | Navajo Plant                        
Commitments and Contingencies                        
Site contingency increase in loss exposure not accrued, best estimate                 1.0      
APS | SCE | Four Corners Units 4 and 5                        
Commitments and Contingencies                        
Disallowance of plant investments   $ 194.0                    
Cost deferrals   $ 215.5                    
Amount not recoverable                 $ 154.4      
4C Acquisition, LLC | Four Corners                        
Commitments and Contingencies                        
Percentage of share of cost of control             7.00%          
BCE | Clear Creek Wind Farm                        
Commitments and Contingencies                        
Equity method investments $ 17.1                 0.0    
Impairment of equity method investments                   $ 12.8    
NTEC | Four Corners                        
Commitments and Contingencies                        
Option to purchase ownership interest (as a percent)       7.00%     7.00%          
Proceeds from operating and maintenance cost reimbursement       $ 70.0                
Asset purchase agreement, option to purchase, ownership interest, percentage       7.00%                
Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste                        
Commitments and Contingencies                        
Amount awarded from other party     $ 14.3               $ 123.9  
Breach of Contract for Disposal of Spent Nuclear Fuel and/or High Level Radioactive Waste | APS                        
Commitments and Contingencies                        
Number of claims submitted | claim                     8  
Amount awarded from other party     $ 4.2               $ 36.0