Derivative financial instruments - Summary of changes in fair value, hedges used to calculate ineffectiveness (Details) - Fair value hedges - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Interest rate risk on finance debt
Disclosure of detailed information about hedges [line items]
Change in fair value of hedging instrument used to calculate ineffectiveness	$ 0	$ 26
Change in fair value of hedged item used to calculate ineffectiveness	0	(27)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	0	1
Interest rate and foreign currency risk on finance debt
Disclosure of detailed information about hedges [line items]
Change in fair value of hedging instrument used to calculate ineffectiveness	(1,417)	3,519
Change in fair value of hedged item used to calculate ineffectiveness	1,356	(3,495)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	$ 61	$ (24)

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfHedgeAccountingLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gain (loss) on the change in fair value of the hedged item used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24B
-Subparagraph a
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24B_a_iv&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24B
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24B_b_i&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainLossOnChangeInFairValueOfHedgedItemUsedAsBasisForRecognisingHedgeIneffectiveness
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The gain (loss) on the change in fair value of the hedging instrument used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24A
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24A_c&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainLossOnChangeInFairValueOfHedgingInstrumentUsedAsBasisForRecognisingHedgeIneffectiveness
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The gain (loss) recognised in profit or loss on hedge ineffectiveness. [Refer: Gain (loss) on hedge ineffectiveness]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24C
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24C_a_i&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24C
-Subparagraph b
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24C_b_ii&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainLossOnHedgeIneffectivenessRecognisedInProfitOrLoss
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	ifrs-full_TypesOfHedgesAxis=ifrs-full_FairValueHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfRisksAxis=ifrs-full_InterestRateRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfRisksAxis=bp_CurrencyAndInterestRateRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: