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Investment Information - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) lots	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) lots	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) lots
Continuous unrealized loss, qualitative disclosures:
Number of positions in an unrealized loss position (lots) | lots	10,400		10,400		9,810
Total number of positions (lots) | lots	13,490		13,490		12,590
Largest single loss	$ 7		$ 7		$ 7
Narrative items:
Equity securities, at fair value	911		911		$ 860
Equity in net (loss) income of investment funds accounted for using the equity method	$ 69	$ 58	$ 117	$ 94
Minimum
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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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