Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 641,678	$ 333,294	$ 1,526,384	$ 992,063
Natural gas
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	641,625	333,256	1,526,202	991,882
Other
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 53	$ 38	$ 182	$ 181