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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount awarded from other party in judgment or settlement of litigation.

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Amount awarded to other party in judgment or settlement of litigation.

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Contingencies and Commitments (Details) - USD ($) $ in Millions	1 Months Ended					6 Months Ended	12 Months Ended
	Mar. 31, 2019	Aug. 31, 2018	Apr. 30, 2018	Dec. 31, 2017	Feb. 28, 2017	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Total environmental accrual included in balance sheet						$ 175	$ 175	$ 178
Letters of Credit Outstanding, Amount						$ 223	223
Ecuador \| Burlington Resources vs The Republic Of Ecuador [Member] \| Burlington Resources, Inc [Member]
Loss Contingencies [Line Items]
Litigation Settlement Amount Awarded To Other Party					$ 42
Litigation Settlement, Amount Awarded from Other Party					$ 380
Offset For Counter Claim				$ 24
Cash Proceeds from Legal Settlements			$ 262	75
Settlement Agreement Payment Installment Total				$ 337
Litigation Settlemen Award Payment Terms						two installments
US and Canada [Member] \| Cleanup Remediation Activities [Member]
Loss Contingencies [Line Items]
Total environmental accrual included in balance sheet						$ 175	175	$ 178
Loss Contingency, Settlement Agreement, Terms						P30Y
Venezuela \| Conoco Phillips Versus Petroleos De Venezuela [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party	$ 8,700
Venezuela \| Conoco Phillips Versus Petroleos De Venezuela 2 [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party			$ 2,000
Cash Proceeds from Legal Settlements							$ 665
Settlement Agreement Payment Installment Total		$ 500
Litigation Settlemen Award Payment Terms						a settlement with PDVSA to recover the full amount of this ICC award, plus interest through the payment period, including initial payments totaling approximately $500 million within a period of 90 days from the time of signing of the settlement agreement. The balance of the settlement is to be paid quarterly over a period of four and a half years.