Fair Value Measurements - Change in Balance Sheet Carrying Value Associated with Level 3 Financial Instruments Carried at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	$ (255)	$ (194)	$ (302)
Total gains/(losses):
Included in earnings	$ 18	$ (104)	$ 84
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Mark-to-market gains (losses) recognized	Mark-to-market gains (losses) recognized	Mark-to-market gains (losses) recognized
Included in other comprehensive income	$ 0	$ 0	$ 0
Settlements	47	43	24
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(190)	(255)	(194)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	65	(62)	(154)
Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	(2)	(4)	(8)
Total gains/(losses):
Included in earnings	1	1	3
Included in other comprehensive income	0	0	0
Settlements	0	1	1
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(1)	(2)	(4)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	1	1	3
Cross-Currency Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	(253)	(190)	(294)
Total gains/(losses):
Included in earnings	17	(105)	81
Included in other comprehensive income	0	0	0
Settlements	47	42	23
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(189)	(253)	(190)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	64	(63)	(157)
Other [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	0	0	0
Total gains/(losses):
Included in earnings	0	0	0
Included in other comprehensive income	0	0	0
Settlements	0	0	0
Transfers in and/or out of level 3	0	0	0
Balance, end of period	0	0	0
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	$ 0	$ 0	$ 0

Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date.

No definition available.

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- Definition

Fair value net derivative asset (liability) measured on recurring basis unobservable input reconciliation gains (losses).

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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-Topic 820
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

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- Definition

Amount of gain (loss) recognized in other comprehensive income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into (out of) level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3).

+ References

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