Derivatives - Narrative (Details) MMBTU in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2020 MMBTU $ / MMBtu	Mar. 31, 2020
Derivative [Line Items]
Target period to cover operating expenses and fixed charges (up to)		2 years
Target period for fixing the price natural gas purchases used in steam operations (up to)		2 years
Subsequent Event | Fixed Price Gas Purchase Swaps (Kern, Delivered)
Derivative [Line Items]
Notional amount, flow rate | MMBTU	10
Derivative, fixed rate | $ / MMBtu	2.79