Debt - Textual (Details) - USD ($) |
6 Months Ended | |||
|---|---|---|---|---|
Jan. 15, 2021 |
Jun. 30, 2021 |
Mar. 31, 2021 |
Dec. 31, 2020 |
|
| Debt [Abstract] | ||||
| Debt balance | $ 20,000,000,000.0 | $ 15,400,000,000 | ||
| Short Term Debt [Line Items] | ||||
| Commercial Paper Program, Amount Outstanding | $ 222,000,000 | |||
| 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 | In May 2021, Moody’s affirmed its rating of our senior long-term debt of “A3” with a “stable” outlook. Moody’s rates our short-term debt as “Prime-2.” | |||
| Fitch, A Rating [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Instrument, Credit Rating | In January 2021, Fitch affirmed its rating of our long-term debt as “A” with a “stable” outlook and affirmed its rating of our short-term debt as “F1+.” | |||
| Standard & Poor's, A Rating [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Instrument, Credit Rating | In January 2021, Fitch affirmed its rating of our long-term debt as “A” with a “stable” outlook and affirmed its rating of our short-term debt as “F1+.” On January 25, 2021, S&P revised its industry risk assessment of the E&P industry to “Moderately High” from “Intermediate” based on a view of increasing risks from the energy transition, price volatility, and weaker profitability. On February 11, 2021, S&P downgraded its rating of our long-term debt from “A” to “A-” with a “stable” outlook and downgraded its rating of our short-term debt from “A-1” to “A-2.” In May 2021, Moody’s affirmed its rating of our senior long-term debt of “A3” with a “stable” outlook. Moody’s rates our short-term debt as “Prime-2.” We do not have any ratings triggers on any of our corporate debt that would cause an automatic default, and thereby impact our access to liquidity, upon downgrade of our credit ratings. If our credit ratings are downgraded from their current levels, it could increase the cost of corporate debt available to us and restrict our access to the commercial paper markets. If our credit rating were to deteriorate to a level prohibiting us from accessing the commercial paper market, we would still be able to access funds under our revolving credit facility | |||
| 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 | $ 5,700,000,000 | |||
| 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 | $ 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 |