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Basis of Presentation - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Sep. 27, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Receivables related to contracts with customers	$ 157,667	$ 145,929
Other receivables	$ 10,727	$ 4,238
CNXM \| Public Unitholders
Business Acquisition [Line Items]
Ownership percentage of public unitholders			46.90%
CNXM \| CNX
Business Acquisition [Line Items]
Ownership percentage by parent			53.10%