XML 53 R71.htm IDEA: XBRL DOCUMENT v3.19.3
Lease Commitments - Narrative (Details)
$ in Millions
 1 Months Ended 3 Months Ended 9 Months Ended
Apr. 30, 2018
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
May 16, 2019
MW
Dec. 31, 2018
USD ($)
Sep. 30, 2016
MW
Sep. 28, 2016
MW
Aug. 31, 2016
MW
Jan. 31, 2016
MW
Jan. 16, 2016
lease
Jan. 15, 2015
lease
Operating Leased Assets [Line Items]                          
Unamortized cost, right-of-way lease payments   $ 60.9   $ 60.9     $ 63.0            
Amortization of prepaid right-of-way agreements   0.9 $ 0.9 2.8 $ 2.8                
Operating leases, capitalized financing costs, investing activities       3.0                  
Finance leases, capitalized financing costs, investing activities       0.4                  
Lessee, operating lease, unguaranteed residual value   22.1   22.1                  
Operating lease, unguaranteed residual value             18.5            
PNM                          
Operating Leased Assets [Line Items]                          
Operating leases, capitalized financing costs, investing activities       1.0                  
Finance leases, capitalized financing costs, investing activities       0.2                  
Lessee, operating lease, unguaranteed residual value   9.3   9.3                  
Operating lease, unguaranteed residual value             $ 7.5            
PNM | Palo Verde Nuclear Generating Station, Unit 1 and 4 Leases                          
Operating Leased Assets [Line Items]                          
Number of leases, expiring | lease                         4
Number of leases under which lease term was extended | lease                         4
Annual lease payments during renewal period       16.5                  
PNM | Palo Verde Nuclear Generating Station, Unit 2 Leases                          
Operating Leased Assets [Line Items]                          
Number of leases, expiring | lease                       4  
Number of leases under which lease term was extended | lease                       1  
Annual lease payments during renewal period       1.6                  
Number of megawatts purchased (in megawatts) | MW               64.1 64.1 64.1 64.1    
Number of megawatts nuclear generation (in megawatts) | MW           114.6   114.6 114.6 114.6      
PNM | Palo Verde Nuclear Generating Station                          
Operating Leased Assets [Line Items]                          
Restriction on conveying, transferring, leasing and dividends             5.00%            
Loss contingency, lease arrangements (up to)   157.6   157.6                  
PNM | Navajo Nation                          
Operating Leased Assets [Line Items]                          
Annual lease payments       6.0                  
Right-of-way lease payments $ 6.9                        
TNMP                          
Operating Leased Assets [Line Items]                          
Operating leases, capitalized financing costs, investing activities       1.9                  
Finance leases, capitalized financing costs, investing activities       0.2                  
Lessee, operating lease, unguaranteed residual value   12.8   12.8                  
Operating lease, unguaranteed residual value             $ 11.0            
Equipment                          
Operating Leased Assets [Line Items]                          
Operating lease, residual value of leased asset   1.7   1.7                  
Equipment | PNM                          
Operating Leased Assets [Line Items]                          
Operating lease, residual value of leased asset   0.6   0.6                  
Equipment | TNMP                          
Operating Leased Assets [Line Items]                          
Operating lease, residual value of leased asset   $ 1.1   $ 1.1                  
New Mexico 2015 Rate Case | PNM | Palo Verde Nuclear Generating Station, Unit 2 Leases                          
Operating Leased Assets [Line Items]                          
Number of megawatts purchased (in megawatts) | MW           64.1