Asset retirement obligations (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Asset retirement obligations (Details)
Asset retirement obligations, beginning of period	$ 5,788,280	$ 230,650
Liabilities assumed in acquisitions	9,508,484	5,251,329
Revision to estimates	(826,405)	0
Accretion expense	929,858	306,301
Asset retirement obligation, end of period	$ 15,364,217	$ 5,788,280

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or develo

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- References

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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- Definition

Amount of asset retirement obligations incurred during the period.

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