Project debt, Details of project debt (Details) - USD ($) $ in Thousands |
Sep. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Project debt [Abstract] | ||
| Cash held to satisfy non-recourse debt agreements | $ 295,000 | $ 296,000 |
| Non-current | 4,093,672 | 4,826,659 |
| Current | 837,675 | 264,455 |
| Total Project debt | $ 4,931,347 | $ 5,091,114 |