XML 162 R113.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Regulatory and Rate Matters - Energy Efficiency and Load Management (Details)
$ in Millions
 12 Months Ended
Apr. 13, 2018
USD ($)
Nov. 08, 2017
USD ($)
Jul. 26, 2017
USD ($)
GWh
Jun. 21, 2017
Apr. 14, 2017
USD ($)
GWh
Jan. 11, 2017
USD ($)
Apr. 15, 2016
USD ($)
GWh
program
Dec. 31, 2019
USD ($)
GWh
Dec. 31, 2018
USD ($)
GWh
Nov. 07, 2017
Public Service Company of New Mexico                    
Public Utilities, General Disclosures [Line Items]                    
Frequency of energy efficiency plan filings       3 years            
Percentage of modification to funding levels       0.10            
Public Service Company of New Mexico | 2017 Energy Efficiency and Load Management Program | Disincentives/Incentives Added                    
Public Utilities, General Disclosures [Line Items]                    
Number of energy efficiency and load management programs (in programs) | program             10      
Program costs related to energy efficiency           $ 26.0 $ 28.0      
Application of incentive based on target savings             $ 2.4      
Minimum profit incentive           $ 1.8   $ 1.8    
Targeted energy savings | GWh             75 59    
Public Service Company of New Mexico | Energy Efficiency and Load Management Program, Proposed 2018 Portfolio | Disincentives/Incentives Added                    
Public Utilities, General Disclosures [Line Items]                    
Program costs related to energy efficiency   $ 23.6     $ 25.1          
Application of incentive based on target savings                 $ 1.9  
Projected earned incentive $ 2.3   $ 1.9   $ 2.1     $ 2.7    
Targeted energy savings | GWh     69   70       53  
Public Utilities, Energy Efficiency and Load Management Programs, Additional Incentive, Targeted Energy Savings | GWh               68    
Public Service Company of New Mexico | Energy Efficiency and Load Management Program, Proposed 2019 Portfolio | Disincentives/Incentives Added                    
Public Utilities, General Disclosures [Line Items]                    
Program costs related to energy efficiency   $ 24.9     $ 28.2          
Application of incentive based on target savings     $ 1.7   $ 2.1     $ 1.8    
Public Service Company of New Mexico | Maximum | Renewable Portfolio Standard                    
Public Utilities, General Disclosures [Line Items]                    
Reasonable cost threshold           3.00%   3.00%    
Sliding scale profit incentive           9.00%        
Public Service Company of New Mexico | Minimum | Renewable Portfolio Standard                    
Public Utilities, General Disclosures [Line Items]                    
Sliding scale profit incentive           7.10%   7.10%    
Measurement Input, Discount Rate                    
Public Utilities, General Disclosures [Line Items]                    
Tax-adjusted WACC   0.0959               0.0771