Acquisitions and Dispositions - Post Acquisition Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Business Acquisition [Line Items]
Earnings (Loss) Before Income Tax	$ 192,862	$ 203,434	$ 350,137	$ 992,965
Operating Segments
Business Acquisition [Line Items]
Revenues	312,768	375,218	1,163,906	1,193,081
Earnings (Loss) Before Income Tax	192,971	85,604	351,799	290,868
CNXM \| Operating Segments
Business Acquisition [Line Items]
Earnings (Loss) Before Income Tax	41,741	31,173	118,739	94,502
CNXM \| Operating Segments \| Midstream Acquisition
Business Acquisition [Line Items]
Earnings (Loss) Before Income Tax	41,741	31,173	118,739	94,502
Midstream Revenue
Business Acquisition [Line Items]
Revenues	18,525	19,946	55,863	69,684
Midstream Revenue \| CNXM \| Operating Segments \| Midstream Acquisition
Business Acquisition [Line Items]
Revenues	$ 74,261	$ 61,372	$ 225,280	$ 186,875

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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