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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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- Definition

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

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

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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.

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Amount of realized and unrealized gain (loss) on investment.

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- Definition

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	$ 257	$ 266
Gain (loss) on equity securities		(1)
Equity investments without readily determinable market value	16	20
Gain on investment	12	5	$ 21
Fair Value, Measurements, Recurring \| Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments, fair value	7	5
Unit investment trust	83	0
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from contingent purchase consideration, asset		1
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring \| Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments, fair value	0	0
Unit investment trust	0	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments, fair value	0	0
Unit investment trust	83	0
Private Insurance and Consulting
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	75	63
Private Equity Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity method investments	182	203
Equity method income	4	7	18
Commitments for potential future investments	117
Equity Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments, fair value	19	16
Gain (loss) on equity securities	1	$ (1)	$ 11
Unit Trust Fund
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gain on investment	7
Unit Trust Fund \| Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unit investment trust	$ 83
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