XML 83 R66.htm IDEA: XBRL DOCUMENT v3.25.3

Commitments and Contingencies (Details) MT in Thousands, MMBTU in Thousands, $ in Millions	9 Months Ended
	Sep. 30, 2025 USD ($) MT well MMBTU	Jun. 30, 2025 MT	Dec. 31, 2024 USD ($)
Operating Leased Assets [Line Items]
Estimated decommissioning costs	$ 126.1
Commitments estimated period	11 years
Supply commitment, volume of LNG | MMBTU	127,951
Supply commitment, volume of LNG supplied per annum | MT	2,450	2,450
Equatorial Guinea
Operating Leased Assets [Line Items]
Number of development wells | well	1
Gulf of America | Bureau Of Ocean Energy Management and Other Third Parties | Surety Bond
Operating Leased Assets [Line Items]
Required performance bonds	$ 153.4		$ 169.4

X

- Definition

Estimated Decommissioning Costs

+ References

No definition available.

+ Details

Name:	kos_EstimatedDecommissioningCosts
Namespace Prefix:	kos_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Estimated Decommissioning Costs, Funding Period

+ References

No definition available.

+ Details

Name:	kos_EstimatedDecommissioningCostsFundingPeriod
Namespace Prefix:	kos_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number Of Development Wells

+ References

No definition available.

+ Details

Name:	kos_NumberOfDevelopmentWells
Namespace Prefix:	kos_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Required Performance Bonds

+ References

No definition available.

+ Details

Name:	kos_RequiredPerformanceBonds
Namespace Prefix:	kos_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Supply Commitment, Volume Of Liquified Natural Gas

+ References

No definition available.

+ Details

Name:	kos_SupplyCommitmentVolumeOfLiquifiedNaturalGas
Namespace Prefix:	kos_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Supply Commitment, Volume Of Liquified Natural Gas, Supplied Per Annum

+ References

No definition available.

+ Details

Name:	kos_SupplyCommitmentVolumeOfLiquifiedNaturalGasSuppliedPerAnnum
Namespace Prefix:	kos_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

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

X

- Details

Name:	srt_StatementGeographicalAxis=country_GQ
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_StatementGeographicalAxis=kos_GulfOfAmericaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CounterpartyNameAxis=kos_BureauOfOceanEnergyManagementAndOtherThirdPartiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_SuretyBondMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: