Long-Term Debt - Additional Information 1 (Detail) - Bank Credit Facility - USD ($)		3 Months Ended
Aug. 14, 2018	Mar. 31, 2019
Debt Instrument [Line Items]
Bank credit facility	$ 700,000,000
Maturity of credit facility	Aug. 14, 2023
Bank credit facility borrowing outstanding		$ 470,000,000
Leverage ratio		400.00%
Current ratio		100.00%
Minimum
Debt Instrument [Line Items]
Commitment fee on unused borrowing base	0.375%
Maximum
Debt Instrument [Line Items]
Commitment fee on unused borrowing base	0.50%
LIBOR \| Minimum
Debt Instrument [Line Items]
Spread rate for interest rate on credit facility	2.00%
LIBOR \| Maximum
Debt Instrument [Line Items]
Spread rate for interest rate on credit facility	3.00%
Base Rate \| Minimum
Debt Instrument [Line Items]
Spread rate for interest rate on credit facility	1.00%
Base Rate \| Maximum
Debt Instrument [Line Items]
Spread rate for interest rate on credit facility	2.00%

Bank credit facility borrowing outstanding.

No definition available.

Name:	crk_BankCreditFacilityBorrowingOutstanding
Namespace Prefix:	crk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Current ratio.

+ References

No definition available.

+ Details

Name:	crk_CurrentRatio
Namespace Prefix:	crk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Leverage ratio.

+ References

No definition available.

+ Details

Name:	crk_LeverageRatio
Namespace Prefix:	crk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: