XML 58 R41.htm IDEA: XBRL DOCUMENT
v3.25.3

Receivables - Narrative (Details) MT in Thousands, $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) MT | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) MT | Sep. 30, 2024 USD ($) | Jun. 30, 2025 MT | Dec. 31, 2024 USD ($)
Oil and Gas Joint Interest Billing Receivables [Line Items] |  |  |  |  |  |
Supply commitment, volume of LNG supplied per annum | MT | 2,450 |  | 2,450 |  | 2,450 |
National Oil Companies of Mauritania And Senegal | Carry Advance Agreements |  |  |  |  |  |
Oil and Gas Joint Interest Billing Receivables [Line Items] |  |  |  |  |  |
Long-term receivables | $ 355.5 |  | $ 355.5 |  |  | $ 280.1
Accrued interest on balance due | 74.6 |  | 74.6 |  |  | $ 56.6
Interest income, long-term notes receivable | $ 6.5 | $ 4.7 | $ 18.0 | $ 14.0 |  |

X
- Definition Interest Income, Long-Term Notes Receivable + References No definition available. + Details
Name: | kos_InterestIncomeLongTermNotesReceivable
Namespace Prefix: | kos_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | kos_OilAndGasJointInterestBillingReceivablesLineItems
Namespace Prefix: | kos_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Oil and Gas, Long-term Receivable + References No definition available. + Details
Name: | kos_OilAndGasLongTermReceivable
Namespace Prefix: | kos_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Oil And Gas Long-Term Receivable, Accrued Interest, Noncurrent + References No definition available. + Details
Name: | kos_OilAndGasLongTermReceivableAccruedInterestNoncurrent
Namespace Prefix: | kos_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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
- Details
Name: | srt_CounterpartyNameAxis=kos_NationalOilCompaniesOfMauritaniaAndSenegalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | kos_OilAndGasOperatingAgreementsAxis=kos_CarryAdvanceAgreementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |