Supplemental Oil and Gas Information (Unaudited) - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020 MMcfe	Dec. 31, 2019 MMcfe	Dec. 31, 2018 MMcfe	Dec. 31, 2017 MMcfe
Oil And Gas In Process Activities [Line Items]
Maximum scheduled drilling term	5 years
Estimation of reserves quantities and future net cash flows description	The proved reserves quantities and future net cash flows were estimated using an unweighted 12-month average pricing based on the prices on the first day of each month during the years ended December 31, 2020, 2019 and 2018, including adjustments related to regional price differentials and energy content.
Revisions of previous estimates, positive revisions due to updates in economic assumptions	381
Revisions of previous estimates, positive revisions due to updates in economic assumptions	1,350
Revisions of previous estimates, negative revisions due to updated forecast of production offset	190
Revisions of previous estimates, negative revisions due to production underperforming	1,162	437
Revisions of previous estimates, extensions discoveries and additions due to addition of proved undeveloped wells		21,548	2,343
Revisions of previous estimates, negative revisions due to updated curves on well		21,095	65,895
Revisions of previous estimates, positive revisions due to increases in pricing			720
Revisions of previous estimates, positive revisions due to production underperforming			6,062	339
Revision of previous estimates, positive revision due to operating expenses			848
Measurement Input, Discount Rate \| Gas And Oil Production
Oil And Gas In Process Activities [Line Items]
Percentage of discount factor to measure future cash flows	0.10

Atlas Growth Partners, L.P. 10-K