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Investment Information - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) lots	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) lots	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) lots
Continuous unrealized loss, qualitative disclosures:
Number of positions in an unrealized loss position (lots) | lots	7,730		7,730		9,980
Total number of positions (lots) | lots	25,020		25,020		20,930
Largest single loss	$ 5		$ 5		$ 8
Narrative items:
Equity securities, at fair value	1,805		1,805		$ 1,675
Equity in net (loss) income of investment funds accounted for using the equity method	$ 134	$ 171	$ 349	$ 437
Minimum
Narrative items:
Time lag for reporting			1 month
Maximum
Narrative items:
Time lag for reporting			3 months

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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