v3.19.3.a.u2

PPAs and other definite-lived intangible assets and liabilities (Tables) | 12 Months Ended
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Dec. 31, 2019
PPAs and other definite-lived intangible assets and liabilities |
Schedule of components of intangible assets subject to amortization | Assets
|  | Other Intangible Assets, Net
|  | Power Purchase |  |  |
|  | Agreements |  | Total
Gross balances, December 31, 2019 |  | $ | 365.6 |  | $ | 365.6
Less: accumulated amortization |  |  | (221.3) |  |  | (221.3)
Net carrying amounts, December 31, 2019 |  | $ | 144.3 |  | $ | 144.3
|  | Other Intangible Assets, Net
|  | Power Purchase |  |  |
|  | Agreements |  | Total
Gross balances, December 31, 2018 |  | $ | 362.7 |  | $ | 362.7
Less: accumulated amortization |  |  | (192.6) |  |  | (192.6)
Net carrying amounts, December 31, 2018 |  | $ | 170.1 |  | $ | 170.1
Liabilities
|  | Power Purchase and Fuel Supply Agreement Liabilities, Net |
|  | Power Purchase |  | Fuel Supply |  |  |  |
|  | Agreements |  | Agreements |  | Total |
Gross balances, December 31, 2019 |  | $ | (28.1) |  |  | (12.6) |  | $ | (40.7) |
Less: accumulated amortization |  |  | 14.4 |  |  | 6.5 |  |  | 20.9 |
Net carrying amounts, December 31, 2019 |  | $ | (13.7) |  | $ | (6.1) |  | $ | (19.8) |
|  | Power Purchase and Fuel Supply Agreement Liabilities, Net |
|  | Power Purchase |  | Fuel Supply |  |  |  |
|  | Agreements |  | Agreements |  | Total |
Gross balances, December 31, 2018 |  | $ | (28.7) |  |  | (12.6) |  | $ | (41.3) |
Less: accumulated amortization |  |  | 14.0 |  |  | 6.1 |  |  | 20.1 |
Net carrying amounts, December 31, 2018 |  | $ | (14.7) |  | $ | (6.5) |  | $ | (21.2) |
Schedule of amortization expense of intangible assets |
|  | 2019 |  | 2018 |  | 2017 |
PPAs |  | $ | 26.4 |  | $ | 43.4 |  | $ | 36.5 |
Fuel supply agreements |  |  | (0.4) |  |  | (0.4) |  |  | (0.4) |
Total amortization |  | $ | 26.0 |  | $ | 43.0 |  | $ | 36.1 |
Schedule of estimated future amortization expense for the next five years |
Year Ended December 31, |  |  |
2020 |  | $ | 22.1 |
2021 |  |  | 20.2 |
2022 |  |  | 15.9 |
2023 |  |  | 12.6 |
2024 |  |  | 12.6 |

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