Investment Information - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) lots	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) lots
Continuous unrealized loss, qualitative disclosures:
Number of positions in an unrealized loss position (lots) | lots	8,380		7,100
Total number of positions (lots) | lots	16,400		15,720
Largest single loss	$ 5		$ 6
Narrative items:
Equity securities, at fair value	1,720		$ 1,186
Equity in net (loss) income of investment funds accounted for using the equity method	$ 99	$ 48
Minimum
Narrative items:
Time lag for reporting	1 month
Maximum
Narrative items:
Time lag for reporting	3 months