XML 62 R50.htm IDEA: XBRL DOCUMENT
v3.26.1

Property and Equipment - Narrative (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Feb. 28, 2026 | Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Dec. 31, 2025
Property, Plant, and Equipment [Line Items] |  |  |  |  |  |
Depletion expense |  | $ 111,800 | $ 141,700 | $ 223,500 | $ 253,100 |
Proved properties |  | 7,763,259 |  | 7,763,259 |  | $ 8,301,679
TEN FPSO |  |  |  |  |  |
Property, Plant, and Equipment [Line Items] |  |  |  |  |  |
Gross purchase price | $ 205,000 |  |  |  |  |
Proved properties |  | $ 88,200 |  | $ 88,200 |  |

X
- Definition Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479908/805-50-55-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480060/805-50-25-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 30 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480027/805-50-30-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 30 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480027/805-50-30-2 + Details
Name: | us-gaap_AssetAcquisitionConsiderationTransferred
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The noncash expense charged against earnings to recognize the consumption of oil and gas reserves that are part of an entities' assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
Name: | us-gaap_DepletionOfOilAndGasProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 905 -SubTopic 360 -Name Accounting Standards Codification -Section 25 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478704/905-360-25-4 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 05 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482338/360-10-05-3 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 30 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482222/360-10-30-2 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 05 -Paragraph 3 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482338/360-10-05-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 05 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482338/360-10-05-3 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 05 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482338/360-10-05-3 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482558/350-40-50-1 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A + Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties with proved reserve accounted for under successful efforts method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 932 -SubTopic 360 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478810/932-360-50-1 + Details
Name: | us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_AssetAcquisitionAxis=kos_TENFPSOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |