CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 70,958	$ 46,445
Other Comprehensive Income:
Actuarially Determined Long-Term Liability Adjustments (Net of tax: ($1,281), ($1,967))	3,997	3,414
Other Comprehensive Income	3,997	3,414
Comprehensive Income	74,955	49,859
Less: Comprehensive Income Attributable to Noncontrolling Interest	8,548	5,452
Comprehensive Income Attributable to CONSOL Energy Inc. Shareholders	$ 66,407	$ 44,407

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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