Acquisitions - Asset Acquisitions - Additional Information (Details) - Gunflint Acquisition $ in Millions	Jan. 11, 2019 USD ($)
Business Acquisition [Line Items]
Percentage of non-operated working interest acquired	9.60%
Purchase price	$ 29.6
Customary purchase price adjustments	$ 27.9

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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