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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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Commercial paper program.

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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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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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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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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 (Narrative) (Details) - USD ($)		12 Months Ended
Debt (Narrative) (Details) - USD ($)	Jan. 15, 2021	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt Instrument Face Amount		$ 17,766,000,000		$ 14,292,000,000
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: “A3” with a “positive” outlook
Fitch, A Rating [Member]
Debt Instrument [Line Items]
Debt Instrument, Credit Rating		Fitch: “A” with a “stable” outlook
Standard & Poor's, A- Rating [Member]
Debt Instrument [Line Items]
Debt Instrument, Credit Rating		S&P: “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
Remaining borrowing capacity under revolving credit facility		$ 6,000,000,000.0
Maturity period of commercial paper (in days)		P90D
Commercial Paper Program, Amount Outstanding		$ 0		0
Commercial Paper Program		6,000,000,000.0
Minimum limit of debt for cross default provision		200,000,000
Letter of Credit [Member]
Short Term Debt [Line Items]
Commercial Paper Program, Capacity		500,000,000
Commercial Paper Program, Amount Outstanding				0
VRDB [Member]
Debt Instrument [Line Items]
Debt Instrument Face Amount		$ 283,000,000		283,000,000
Conoco Phillips Commercial Paper Program [Member] \| Commercial Paper [Member]
Short Term Debt [Line Items]
Commercial Paper Program, Amount Outstanding				$ 300,000,000