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Percent of notes offered tendered and exchanged for new debt.

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Tendered and exchanged notes for new debt.

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Minimum limit of debt for cross default provision.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of short-term and long-term debt and lease obligation.

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Description of the credit rating indicative of likelihood of repayment of the debt instrument given by a credit rating agency (for example, Standard and Poor's, Moody's, Fitch).

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Face (par) amount of debt instrument at time of issuance.

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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.

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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 of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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Date the credit facility terminates, in YYYY-MM-DD format.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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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.

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Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

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Debt - Textual (Details) - USD ($)		9 Months Ended
Debt - Textual (Details) - USD ($)	Jan. 15, 2021	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt [Abstract]
Debt balance		$ 19,700,000,000		$ 15,400,000,000
Short Term Debt [Line Items]
Commercial Paper Program, Amount Outstanding		$ 281,000,000
Concho Resources Incorporated [Member]
Debt Instrument [Line Items]
Adjustment to fair value of the senior notes	$ 800,000,000
Long-term debt	4,696,000,000
Business Combination, Notes Offered In Exchange	$ 3,900,000,000		$ 3,900,000,000
Business Combination, Percent Of Notes Offered Tendered And Exchanged For New Debt			98.00%
Business Combination, Tendered And Exchanged Notes For New Debt			$ 3,800,000,000
Debt Instrument Face Amount			$ 67,000,000
Moody's, A3 Rating [Member]
Debt Instrument [Line Items]
Debt Instrument, Credit Rating		Moody’s affirmed its rating of our senior long-term debt of “A3” and upgraded the outlook to “positive” from “stable.”
Fitch, A Rating [Member]
Debt Instrument [Line Items]
Debt Instrument, Credit Rating		Fitch affirmed its rating of our long-term debt as “A” with a “stable” outlook.
Standard & Poor's, A Rating [Member]
Debt Instrument [Line Items]
Debt Instrument, Credit Rating		S&P affirmed its rating of our long-term debt of “A-” with a “stable” outlook.
Revolving Credit Facility [Member]
Short Term Debt [Line Items]
Maximum borrowing capacity under revolving credit facility		$ 6,000,000,000.0
Line of credit facility, expiration date		May 31, 2023
Remaining borrowing capacity under revolving credit facility		$ 6,000,000,000.0
Commercial Paper Program, Amount Outstanding		0		0
Minimum limit of debt for cross default provision		200,000,000
Letter of Credit [Member]
Short Term Debt [Line Items]
Commercial Paper Program, Amount Outstanding		0		0
Letter of Credit [Member] \| Maximum [Member]
Short Term Debt [Line Items]
Commercial Paper Program, Capacity		500,000,000
VRDB [Member]
Debt Instrument [Line Items]
Debt Instrument Face Amount		283,000,000
Conoco Phillips Commercial Paper Program [Member] \| Commercial Paper [Member]
Short Term Debt [Line Items]
Maximum borrowing capacity under revolving credit facility		$ 6,000,000,000.0
Commercial Paper Program, Amount Outstanding				$ 300,000,000
Conoco Phillips Commercial Paper Program [Member] \| Commercial Paper [Member] \| Maximum [Member]
Short Term Debt [Line Items]
Maturity period of commercial paper (in days)		maturities of 90 days