Derivative and Financial Instruments - Schedule of Debt Securities Carried at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Cash and Cash Equivalents	$ 6,974	$ 6,458
Short-Term Investments	1,635	2,785
Investments and Long-Term Receivables	8,197	8,225
Within one year \| Reported Value Measurement
Debt Securities, Available-for-sale [Line Items]
Cash and Cash Equivalents	113	97
Short-Term Investments	543	603
Within one year \| Reported Value Measurement \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cash and Cash Equivalents	0	0
Short-Term Investments	307	323
Within one year \| Reported Value Measurement \| Commercial Paper
Debt Securities, Available-for-sale [Line Items]
Cash and Cash Equivalents	101	97
Short-Term Investments	136	156
Within one year \| Reported Value Measurement \| U.S. Government Obligations
Debt Securities, Available-for-sale [Line Items]
Cash and Cash Equivalents	12	0
Short-Term Investments	87	115
Within one year \| Reported Value Measurement \| U.S. Government Agency Obligations
Debt Securities, Available-for-sale [Line Items]
Short-Term Investments	13	8
Within one year \| Reported Value Measurement \| Foreign Government Obligations
Debt Securities, Available-for-sale [Line Items]
Short-Term Investments	0	0
Within one year \| Reported Value Measurement \| Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Short-Term Investments	0	1
Investments and Long-Term Receivables \| Reported Value Measurement
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	612	522
Investments and Long-Term Receivables \| Reported Value Measurement \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	391	309
Investments and Long-Term Receivables \| Reported Value Measurement \| U.S. Government Obligations
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	96	63
Investments and Long-Term Receivables \| Reported Value Measurement \| U.S. Government Agency Obligations
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	7	5
Investments and Long-Term Receivables \| Reported Value Measurement \| Foreign Government Obligations
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	7	7
Investments and Long-Term Receivables \| Reported Value Measurement \| Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Investments and Long-Term Receivables	$ 111	$ 138

Amount of investments including trading securities, held-to-maturity securities, and short-term investments classified as other and current but excluding investement in Cenovus Energy Common Shares.

No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 210
-SubTopic 10
-Section S99
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