XML 136 R128.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Supplemental Oil and Gas Information - Principal Sources of Change in the Standardized Measure of Discounted Future Net Cash Flows (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Oil and Gas Exploration and Production Industries Disclosures [Abstract] |  |  |  |
Net changes in prices and production costs | $ (2,993.9) | $ 2,972.6 | $ 2,428.4 |
Net changes in development costs | (675.7) | (1,891.1) | (724.4) |
Sales and transfers of oil and natural gas produced, net of production costs | (2,163.8) | (1,978.6) | (1,576.0) |
Net change due to extensions and discoveries | 1,221.9 | 1,930.3 | 807.9 |
Net change due to purchases and sales of proved reserves | (628.1) | 3,152.4 | 85.9 |
Development costs incurred | 1,282.4 | 1,017.3 | 802.7 |
Accretion of discount | 1,002.0 | 469.5 | 270.9 |
Revisions of previous quantity estimates | (71.2) | (347.8) | (109.5) |
Net change in income taxes | 574.1 | (967.6) | (643.0) |
Net increase (decrease) | (2,452.3) | 4,357.0 | 1,342.9 |
Standardized measure | $ 5,827.6 | $ 8,279.9 | $ 3,922.9 | $ 2,580.0

X
- Definition Development Costs Incurred During Period + References No definition available. + Details
Name: | mur_DevelopmentCostsIncurredDuringPeriod
Namespace Prefix: | mur_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Increase Decrease Due To Purchases and Sales of Minerals in Place + References No definition available. + Details
Name: | mur_IncreaseDecreaseDueToPurchasesAndSalesOfMineralsInPlace
Namespace Prefix: | mur_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of extensions, discoveries and improved recovery of proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 + Details
Name: | srt_ExtensionsDiscoveriesAdditionsAndImprovedRecoveryLessRelatedCosts
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of change in estimated future development costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 + Details
Name: | srt_IncreaseDecreaseInEstimatedFutureDevelopmentCosts
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of change in the estimated future income tax on future pretax net cash flows related to the entity's proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 + Details
Name: | srt_IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of change in sales and transfer prices and in production (lifting) costs related to future production. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 + Details
Name: | srt_NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of revisions of estimated quantity of oil and gas in proved reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 + Details
Name: | srt_RevisionsOfPreviousQuantityEstimates
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of (increase) decrease in standardized measure of discounted future net cash flow as a result of sales and transfers of oil and gas produced. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 + Details
Name: | srt_SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow relating to proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 + Details
Name: | srt_StandardizedMeasureOfDiscountedFutureNetCashFlowOfProvedOilAndGasReservesPeriodIncreaseDecrease
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of accretion of discount for the standardized measure of discounted future net cash flow related to proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35A -URI http://asc.fasb.org/extlink&oid=68064819&loc=SL6807758-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63123-109448 + Details
Name: | srt_StandardizedMeasureOfDiscountedFutureNetCashFlowRelatingToProvedOilAndGasReservesAccretionOfDiscount
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of discounted future accumulated cash inflow relating to proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Form 20-F -Section Item 18 -Subsection Instruction 2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62455-109447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62424-109447 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 55 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=34713648&loc=d3e63094-109448 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62500-109447 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62479-109447 + Details
Name: | srt_StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves
Namespace Prefix: | srt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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