Represents authorized amount of stock and debt repurchase program.

No definition available.

Name:	ceix_StockAndDebtRepurchaseProgramAuthorizedAmount
Namespace Prefix:	ceix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Stock And Debt Repurchase Program Authorized Expansion Amount

+ References

No definition available.

+ Details

Name:	ceix_StockAndDebtRepurchaseProgramAuthorizedExpansionAmount
Namespace Prefix:	ceix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Stock And Debt Repurchase Program Available Capacity

+ References

No definition available.

+ Details

Name:	ceix_StockAndDebtRepurchaseProgramAvailableCapacity
Namespace Prefix:	ceix_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(15)(5))
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-Name Accounting Standards Codification
-Topic 210
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(15)(5))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 26, 2023	May 02, 2023	Apr. 27, 2023	Mar. 31, 2023	Aug. 01, 2022	Mar. 31, 2022
Subsequent Event [Line Items]
Aggregate authorized amount					$ 600,000
Senior Secured Second Lien Notes due 2025 \| Senior Notes
Subsequent Event [Line Items]
Debt instrument, repurchased face amount				$ 50,000		$ 25,000
Subsequent Event
Subsequent Event [Line Items]
Stock and debt repurchase program expansion amount			$ 400,000
Aggregate authorized amount			$ 1,000,000
Stock And Debt Repurchase Program Available Capacity		$ 705,000
Dividends payable, amount per share (in dollars per share)		$ 1.10
Dividends payable		$ 37,000
Subsequent Event \| Senior Secured Second Lien Notes due 2025 \| Senior Notes
Subsequent Event [Line Items]
Debt instrument, redemption price, percentage	102.75%
Debt instrument, repurchased face amount	$ 25,000