Fair Value Hierarchy - Investments, Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net realized gains/(losses)	$ (163)	$ (72)	$ (215)	$ (128)
Investments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net realized gains/(losses)	113	103	344	428
Net unrealized gains/(losses)	(346)	(407)	(904)	(1,828)
Investments \| Operating income (loss)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net realized gains/(losses)	(385)	(427)	(1,030)	(1,710)
Investments \| Interest income
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net realized gains/(losses)	152	123	470	314
Investments \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Net realized gains/(losses)	$ (233)	$ (304)	$ (560)	$ (1,400)

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.

No definition available.

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- Definition

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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