Fair Value of Financial Instruments - Carrying Amounts (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Fair value disclosure
Loss on equity securities	$ 19
Fair Value, Inputs, Level 1 \| Carrying Amount
Fair value disclosure
Equity securities	3	$ 22
Fair Value, Inputs, Level 1 \| Fair Value
Fair value disclosure
Equity securities	3	22
Fair Value Inputs, Level 2 \| Carrying Amount
Fair value disclosure
Long-term debt, excluding finance lease and other obligations	19,590	20,255
Fair Value Inputs, Level 2 \| Fair Value
Fair value disclosure
Long-term debt, excluding finance lease and other obligations	13,439	17,309
Fair Value, Inputs, Level 3 \| Carrying Amount
Fair value disclosure
Indemnifications related to the sale of the Latin American business	86	86
Fair Value, Inputs, Level 3 \| Fair Value
Fair value disclosure
Indemnifications related to the sale of the Latin American business	$ 86	$ 86

Disposal Group, Including Discontinued Operation, Fair Value of Indemnification

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

Reference 2: 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(2))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714

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- Definition

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.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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