Financial Instruments, Fair Value Measurement, Credit Risk and Foreign Exchange Risk - Commodity Price Risk (Details) - Forecast - Commodity Hedge - Collars: January 1, to June 30, 2020	6 Months Ended
	Jun. 30, 2020 $ / bbl $ / collar bbl
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Volume (in barrels of oil per day) | bbl	6,000
Purchased | Put
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Floor price (in dollars per barrel) | $ / bbl	55.00
Sold | Call
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Cap Price | $ / collar	69.05