XML 153 R181.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Commitments and Contingencies - Commitments (Details)
$ in Millions, $ in Millions
 12 Months Ended
Dec. 31, 2019
CAD ($)
Dec. 31, 2018
CAD ($)
Dec. 31, 2017
CAD ($)
Dec. 31, 2019
USD ($)
Jan. 01, 2019
CAD ($)
Dec. 17, 2018
Jul. 30, 2015
USD ($)
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements $ 217            
Long-term service agreements 150            
Non-cancellable operating leases 77 $ 80     $ 83    
Growth 1,268            
TransAlta Energy Transition Bill 24           $ 55
Total 3,879            
Sublease payments received (amounts less than)   $ 1 $ 1        
Funded portion of Energy Bill commitment       $ 37      
Litigation settlement, amount awarded from other party 27            
Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 2,122            
Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 21            
2020              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 147            
Long-term service agreements 50            
Non-cancellable operating leases 4            
Growth 535            
TransAlta Energy Transition Bill 6            
Total 876            
2020 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 125            
2020 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 9            
2021              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 16            
Long-term service agreements 22            
Non-cancellable operating leases 2            
Growth 254            
TransAlta Energy Transition Bill 6            
Total 430            
2021 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 125            
2021 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 5            
2022              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 16            
Long-term service agreements 32            
Non-cancellable operating leases 2            
Growth 196            
TransAlta Energy Transition Bill 6            
Total 376            
2022 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 120            
2022 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 4            
2023              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 16            
Long-term service agreements 17            
Non-cancellable operating leases 2            
Growth 270            
TransAlta Energy Transition Bill 6            
Total 442            
2023 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 128            
2023 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 3            
2024              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 8            
Long-term service agreements 15            
Non-cancellable operating leases 3            
Growth 13            
TransAlta Energy Transition Bill 0            
Total 170            
2024 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 131            
2024 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 0            
2025              
Disclosure of Commitments [Line Items]              
Coal supply and mining agreements 14            
Long-term service agreements 14            
Non-cancellable operating leases 64            
Growth 0            
TransAlta Energy Transition Bill 0            
Total 1,585            
2025 | Natural gas, transportation and other contracts              
Disclosure of Commitments [Line Items]              
Purchase obligations 1,493            
2025 | Transmission              
Disclosure of Commitments [Line Items]              
Purchase obligations 0            
Line loss rule proceeding              
Disclosure of Commitments [Line Items]              
Estimated financial effect of contingent liabilities $ 12            
Tidewater Brazeau River Pipeline | Tidewater              
Disclosure of Commitments [Line Items]              
Future option to acquire pipeline, ownership percentage           50.00%