Project debt, Repayment schedule (Details) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|---|
| Repayment schedule [Abstract] | |||
| Project debt | $ 5,237,614 | $ 4,852,348 | $ 5,091,114 |
| 2020 [Member] | |||
| Repayment schedule [Abstract] | |||
| Interest repayment | 19,287 | 12,799 | |
| Nominal repayment | 293,059 | 256,620 | |
| 2021 [Member] | |||
| Repayment schedule [Abstract] | |||
| Project debt | 328,364 | 262,787 | |
| 2022 [Member] | |||
| Repayment schedule [Abstract] | |||
| Project debt | 355,806 | 293,642 | |
| 2023 [Member] | |||
| Repayment schedule [Abstract] | |||
| Project debt | 371,548 | 319,962 | |
| 2024 [Member] | |||
| Repayment schedule [Abstract] | |||
| Project debt | 508,843 | 335,067 | |
| Subsequent Years [Member] | |||
| Repayment schedule [Abstract] | |||
| Project debt | $ 3,360,707 | $ 3,371,724 |