v3.25.4

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jan. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	$ 301	$ 257
Exchange traded equity securities	12	7
Gain (loss) on equity securities			$ (1)
Equity investments without readily determinable market value	17	16
Unit investment trust	0	83
Investment income	34	12	5
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	220	182
Gain related to investments in private equity funds and other investments	30	4	7
Commitments for potential future investments	101
Private Insurance and Consulting
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	81	75
Equity Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Exchange traded equity securities	24	19
Gain (loss) on equity securities	$ 4	1	$ (1)
Unit Trust Fund
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Disposal of investment				$ 83
Unit investment trust		83
Investment income		$ 7
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revenue target period (in years)	2 years	2 years
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revenue target period (in years)	4 years	4 years

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