Property and equipment - Costs Incurred in the Acquisition, Exploration and Development of Oil and Natural Gas Properties (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2021 |
Jun. 30, 2020 |
Jun. 30, 2021 |
Jun. 30, 2020 |
|
Property acquisition costs: | ||||
Evaluated | $ 0 | $ 0 | $ 0 | $ 7,586 |
Unevaluated | 0 | 912 | 0 | 16,468 |
Exploration costs | 15,313 | 3,374 | 19,270 | 10,084 |
Development costs | 87,509 | 72,567 | 152,001 | 218,725 |
Total oil and natural gas properties incurred capital expenditures | $ 102,822 | $ 76,853 | $ 171,271 | $ 252,863 |