Stock-Based Compensation - Schedule of Total Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 38	$ 55	$ 85	$ 86
Total stock-based compensation expense	41	55	149	86
Income Statement Location [Axis]: comp:TechnologyAndDevelopmentExpense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	13	25	32	38
Income Statement Location [Axis]: us-gaap:BusinessCombinationIntegrationRelatedCosts
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Anywhere merger transaction and integration expenses	3	0	64	0
Income Statement Location [Axis]: us-gaap:GeneralAndAdministrativeExpense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	13	11	25	17
Income Statement Location [Axis]: us-gaap:OtherCostAndExpenseOperating
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	8	10	18	15
Income Statement Location [Axis]: us-gaap:OtherSellingAndMarketingExpense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	4	9	9	16
Income Statement Location [Axis]: us-gaap:SalesCommissionsAndFees
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation	$ 0	$ 0	$ 1	$ 0

Share-Based Payment Arrangement, Expense, Including Merger And Integration Costs

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- Definition

Share-Based Payment Arrangement, Expense, Merger And Integration Costs

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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