CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - Parenthetical - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Actuarially Determined Long-Term Liability Adjustments, Tax	$ 781	$ 1,281
Retirement of common stock (in shares)	0	44,000
Consol Coal Resources LP Units
Retirement of common stock (in shares)	0	0

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration