Represents authorized amount of stock and debt repurchase program.

No definition available.

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Namespace Prefix:	ceix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

+ Details

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Period Type:	duration

- Definition

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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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Details

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Period Type:

- Details

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Stock and Debt Repurchases - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2022	Apr. 30, 2023	Dec. 31, 2022	Nov. 30, 2017
Class of Stock [Line Items]
Aggregate authorized amount						$ 1,000,000
Stock repurchased and retired during period, shares	1,547,846	1,225,134	1,207,409	3,980,389
Treasury stock acquired, average cost per share (in dollars per share)				$ 67.68
Stock repurchased during period (in shares)					0
Senior Secured Second Lien Notes due 2025
Class of Stock [Line Items]
Repayments of debt				$ 101,832	$ 26,387
Senior Notes \| Senior Secured Second Lien Notes due 2025
Class of Stock [Line Items]
Debt instrument, interest rate, stated percentage	11.00%			11.00%			11.00%	11.00%
Repayments of debt				$ 101,832	26,387
Debt instrument, repurchased face amount	$ 99,107			$ 99,107	$ 25,000