Revenue (Disaggregation) (Details) - CAD ($) $ in Millions | 12 Months Ended |
Dec. 31, 2020 | Dec. 31, 2019 |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | $ 5,506 | $ 6,111 |
Total operating revenues | 5,506 | 6,111 |
Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 2,480 | 2,607 |
Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 1,494 | 1,430 |
Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 474 | 744 |
Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 1,058 | 1,119 |
Other | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 29 | 282 |
Operating | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 5,506 | 6,111 |
Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 2,480 | 2,607 |
Total operating revenues | 2,473 | 2,596 |
Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,494 | 1,430 |
Total operating revenues | 1,494 | 1,429 |
Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 474 | 744 |
Total operating revenues | 474 | 744 |
Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,058 | 1,119 |
Total operating revenues | 1,051 | 1,097 |
Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 29 | 282 |
Total operating revenues | 14 | 245 |
Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | (29) | (71) |
Total operating revenues | (19) | (43) |
Eliminations | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 7 | 11 |
Eliminations | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 1 |
Eliminations | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Eliminations | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 7 | 22 |
Eliminations | Other | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 15 | 37 |
Non-Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 30 | 261 |
Total operating revenues | 30 | 261 |
Non-Regulated | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 38 |
Non-Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Non-Regulated | Operating | Florida Electric Utility | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Non-Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Non-Regulated | Operating | Canadian Electric Utilities | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Non-Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Non-Regulated | Operating | Other Electric Utilities | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Non-Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 16 | 16 |
Non-Regulated | Operating | Gas Utilities and Infrastructure | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Non-Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 29 | 282 |
Non-Regulated | Operating | Other | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 38 |
Non-Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | (15) | (37) |
Non-Regulated | Eliminations | Capacity | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Electric | Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 4,442 | 4,769 |
Total operating revenues | 4,442 | 4,769 |
Electric | Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 2,480 | 2,607 |
Electric | Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,494 | 1,430 |
Electric | Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 474 | 744 |
Electric | Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1 | 0 |
Electric | Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | (7) | (12) |
Electric | Regulated | Residential | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 2,350 | 2,409 |
Electric | Regulated | Residential | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,365 | 1,387 |
Electric | Regulated | Residential | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 806 | 746 |
Electric | Regulated | Residential | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 179 | 276 |
Electric | Regulated | Residential | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Residential | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Residential | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Commercial | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,316 | 1,484 |
Electric | Regulated | Commercial | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 678 | 745 |
Electric | Regulated | Commercial | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 405 | 400 |
Electric | Regulated | Commercial | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 233 | 339 |
Electric | Regulated | Commercial | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Commercial | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Commercial | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Industrial | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 434 | 461 |
Electric | Regulated | Industrial | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 178 | 207 |
Electric | Regulated | Industrial | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 224 | 210 |
Electric | Regulated | Industrial | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 32 | 44 |
Electric | Regulated | Industrial | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Industrial | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Industrial | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Other Electric And Regulatory | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 281 | 304 |
Electric | Regulated | Other Electric And Regulatory | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 242 | 246 |
Electric | Regulated | Other Electric And Regulatory | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 31 | 45 |
Electric | Regulated | Other Electric And Regulatory | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 8 | 13 |
Electric | Regulated | Other Electric And Regulatory | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Other Electric And Regulatory | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Electric | Regulated | Other Electric And Regulatory | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,034 | 1,081 |
Total operating revenues | 1,034 | 1,081 |
Gas | Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 1,041 | 1,103 |
Gas | Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | (7) | (22) |
Gas | Regulated | Residential | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 495 | 502 |
Gas | Regulated | Residential | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Residential | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Residential | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Residential | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 495 | 502 |
Gas | Regulated | Residential | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Residential | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Commercial | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 275 | 298 |
Gas | Regulated | Commercial | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Commercial | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Commercial | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Commercial | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 275 | 298 |
Gas | Regulated | Commercial | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Commercial | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Industrial | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 54 | 50 |
Gas | Regulated | Industrial | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Industrial | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Industrial | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Industrial | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 54 | 50 |
Gas | Regulated | Industrial | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Industrial | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 149 | 171 |
Gas | Regulated | Other | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 156 | 193 |
Gas | Regulated | Other | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Gas | Regulated | Other | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | (7) | (22) |
Marketing and trading margin | Non-Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 38 | 31 |
Marketing and trading margin | Non-Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Marketing and trading margin | Non-Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Marketing and trading margin | Non-Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Marketing and trading margin | Non-Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Marketing and trading margin | Non-Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 38 | 31 |
Marketing and trading margin | Non-Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Energy sales | Non-Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 68 |
Energy sales | Non-Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Energy sales | Non-Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Energy sales | Non-Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Energy sales | Non-Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Energy sales | Non-Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 16 | 80 |
Energy sales | Non-Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | (16) | (12) |
Finance Income | Regulated | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 61 | 60 |
Finance Income | Regulated | Operating | Florida Electric Utility | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Finance Income | Regulated | Operating | Canadian Electric Utilities | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Finance Income | Regulated | Operating | Other Electric Utilities | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Finance Income | Regulated | Operating | Gas Utilities and Infrastructure | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 61 | 60 |
Finance Income | Regulated | Operating | Other | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Finance Income | Regulated | Eliminations | Repsol Energy Canada | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Other | Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 61 | 111 |
Other | Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 17 | 22 |
Other | Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 28 | 29 |
Other | Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 22 | 72 |
Other | Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 1 | 0 |
Other | Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | 0 | 0 |
Other | Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Total operating revenues | (7) | (12) |
Other | Non-Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 37 | 22 |
Other | Non-Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Other | Non-Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Other | Non-Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | 0 |
Other | Non-Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 16 | 16 |
Other | Non-Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 21 | 31 |
Other | Non-Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue from contract with customer | 0 | (25) |
Mark-To-Market | Non-Regulated | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | (45) | 102 |
Mark-To-Market | Non-Regulated | Operating | Florida Electric Utility | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Mark-To-Market | Non-Regulated | Operating | Canadian Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Mark-To-Market | Non-Regulated | Operating | Other Electric Utilities | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Mark-To-Market | Non-Regulated | Operating | Gas Utilities and Infrastructure | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | 0 | 0 |
Mark-To-Market | Non-Regulated | Operating | Other | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | (46) | 102 |
Mark-To-Market | Non-Regulated | Eliminations | | |
Disaggregation of Revenue [Line Items] | | |
Revenue which does not represent revenues from contracts with customers | $ 1 | $ 0 |