Commitments, Contingencies and Off-Balance Sheet Arrangements - Contractual Obligations (Detail) $ in Millions	Sep. 30, 2026 USD ($)
Senior Notes
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	$ 0
Contractual Obligations, Payments Due by Period, 2027	750
Contractual Obligations, Payments Due by Period, 2028	0
Contractual Obligations, Payments Due by Period, 2029	750
Contractual Obligations, Payments Due by Period, 2030	0
Contractual Obligations, Payments Due by Period, Thereafter	8,050
Contractual Obligations, Payments Due by Period, Total	9,550
Note Purchase Agreements
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	0
Contractual Obligations, Payments Due by Period, 2027	478
Contractual Obligations, Payments Due by Period, 2028	200
Contractual Obligations, Payments Due by Period, 2029	350
Contractual Obligations, Payments Due by Period, 2030	466
Contractual Obligations, Payments Due by Period, Thereafter	1,189
Contractual Obligations, Payments Due by Period, Total	2,683
Credit Agreement
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	630
Contractual Obligations, Payments Due by Period, 2027	0
Contractual Obligations, Payments Due by Period, 2028	0
Contractual Obligations, Payments Due by Period, 2029	0
Contractual Obligations, Payments Due by Period, 2030	0
Contractual Obligations, Payments Due by Period, Thereafter	0
Contractual Obligations, Payments Due by Period, Total	630
Premium Financing Debt Facility
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	228
Contractual Obligations, Payments Due by Period, 2027	0
Contractual Obligations, Payments Due by Period, 2028	0
Contractual Obligations, Payments Due by Period, 2029	0
Contractual Obligations, Payments Due by Period, 2030	0
Contractual Obligations, Payments Due by Period, Thereafter	0
Contractual Obligations, Payments Due by Period, Total	228
Interest on debt
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	80
Contractual Obligations, Payments Due by Period, 2027	593
Contractual Obligations, Payments Due by Period, 2028	539
Contractual Obligations, Payments Due by Period, 2029	529
Contractual Obligations, Payments Due by Period, 2030	473
Contractual Obligations, Payments Due by Period, Thereafter	6,117
Contractual Obligations, Payments Due by Period, Total	8,331
Total debt obligations
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	938
Contractual Obligations, Payments Due by Period, 2027	1,821
Contractual Obligations, Payments Due by Period, 2028	739
Contractual Obligations, Payments Due by Period, 2029	1,629
Contractual Obligations, Payments Due by Period, 2030	939
Contractual Obligations, Payments Due by Period, Thereafter	15,356
Contractual Obligations, Payments Due by Period, Total	21,422
Operating lease obligations
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	35
Contractual Obligations, Payments Due by Period, 2027	167
Contractual Obligations, Payments Due by Period, 2028	131
Contractual Obligations, Payments Due by Period, 2029	100
Contractual Obligations, Payments Due by Period, 2030	88
Contractual Obligations, Payments Due by Period, Thereafter	237
Contractual Obligations, Payments Due by Period, Total	758
Less sublease arrangements
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, Thereafter	0
Contractual Obligations, Sublease Arrangement, 2026	(1)
Contractual Obligations, Sublease Arrangement, 2027	(3)
Contractual Obligations, Sublease Arrangement, 2028	(2)
Contractual Obligations, Sublease Arrangement, 2029	(2)
Contractual Obligations, Sublease Arrangement, 2030	(1)
Contractual Obligations, Sublease Arrangement, Total	(9)
Outstanding purchase obligations
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	111
Contractual Obligations, Payments Due by Period, 2027	502
Contractual Obligations, Payments Due by Period, 2028	113
Contractual Obligations, Payments Due by Period, 2029	67
Contractual Obligations, Payments Due by Period, 2030	39
Contractual Obligations, Payments Due by Period, Thereafter	84
Contractual Obligations, Payments Due by Period, Total	916
Total contractual obligations
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Contractual Obligations, Payments Due by Period, 2026	1,083
Contractual Obligations, Payments Due by Period, 2027	2,487
Contractual Obligations, Payments Due by Period, 2028	981
Contractual Obligations, Payments Due by Period, 2029	1,794
Contractual Obligations, Payments Due by Period, 2030	1,065
Contractual Obligations, Payments Due by Period, Thereafter	15,677
Contractual Obligations, Payments Due by Period, Total	$ 23,087

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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- Definition

Recorded unconditional purchase obligation receivable.

+ References

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- Definition

Recorded unconditional purchase obligation receivable in fifth year.

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Recorded unconditional purchase obligation receivable in fourth year.

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Recorded unconditional purchase obligation receivable in second year.

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No definition available.

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Recorded unconditional purchase obligation receivable in third year.

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- Definition

Recorded unconditional purchase obligation receivable within one year.

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No definition available.

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- Definition

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-6

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- Definition

Amount of recorded unconditional purchase obligation maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-6

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- Definition

Amount of recorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of recorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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