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Investment Information - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2025 USD ($) lots	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) lots
Continuous unrealized loss, qualitative disclosures:
Number of positions in an unrealized loss position (lots) | lots	10,420		9,980
Total number of positions (lots) | lots	21,650		20,930
Largest single loss	$ 5		$ 8
Narrative items:
Equity securities, at fair value	1,618		$ 1,675
Equity in net (loss) income of investment funds accounted for using the equity method	$ 53	$ 99
Minimum
Narrative items:
Time lag for reporting	1 month
Maximum
Narrative items:
Time lag for reporting	3 months

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Disclosure regarding factors used to determine that the impairment of securities categorized as available for sale securitie.This item contains disclosure of the largest single loss position in a single lot as of the balance sheet date.

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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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