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Amount of investment in equity security without readily determinable fair value.

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Payments of cash to employees, including wages and salaries, during the current period.

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RELATED PARTIES (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
RELATED PARTIES (Details) - USD ($) $ in Millions	Sep. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Apr. 30, 2025
Related Party Transaction [Line Items]
Non-marketable equity securities		$ 53		$ 53		$ 48
Equity method investments		20		20		$ 20
Revenue		883	$ 1,567	1,603	$ 2,720
Mainstay Labs, Inc.
Related Party Transaction [Line Items]
Non-marketable equity securities		48		48
Mainstay Labs, Inc. \| Certain Employees, Excluding Management
Related Party Transaction [Line Items]
Payments to Employees			0		0
Mainstay Labs, Inc. \| Series A Preferred Stock
Related Party Transaction [Line Items]
Preferred stock as consideration receivables	$ 9
Related Party \| Mainstay Labs, Inc. \| Mainstay National Title LLC
Related Party Transaction [Line Items]
Ownership percentage, joint venture							25.00%
Equity method investments		1		1
Revenue		$ 2	$ 4	$ 5	$ 4
Related Party \| Common Stock \| Mainstay Labs, Inc.
Related Party Transaction [Line Items]
Shares issued during period (in shares)		8,384		21,307