Expenses - Restructuring Reserve (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Restructuring Reserve [Roll Forward]
Beginning balance	$ 96	$ 208	$ 88
Net repositioning benefit	326	(2)	203
Payments and Other Adjustments	(214)	(110)	(83)
Ending balance	208	96	208
Labor And Related Expense
Restructuring Reserve [Roll Forward]
Net repositioning benefit		(15)
Occupancy, Net
Restructuring Reserve [Roll Forward]
Net repositioning benefit		13
Employee Related Costs
Restructuring Reserve [Roll Forward]
Beginning balance	96	207	83
Net repositioning benefit	211	(15)	182
Payments and Other Adjustments	(99)	(96)	(58)
Ending balance	208	96	207
Other
Restructuring Reserve [Roll Forward]
Beginning balance	0	1	5
Net repositioning benefit	115	13	21
Payments and Other Adjustments	(115)	(14)	(25)
Ending balance	$ 0	$ 0	$ 1

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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