Investments - Repurchase Agreements (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	$ 4,477	$ 3,110
Amortized Cost	5,694	2,923
Fair Value	4,606	3,208
Securities Purchased under Agreements to Resell, Fair Value of Collateral	616
Securities Purchased under Agreements to Resell	26
Maturity Overnight and on Demand
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	0	0
Maturity Less than 30 Days
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	150	2,512
Maturity 30 to 90 Days
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	1,260	0
Maturity Greater than 90 Days
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	201	0
Maturity Greater than 1 Year [Member]
Schedule of Repurchase Agreements [Line Items]
Payables for repurchase agreements	2,866	598
Available-for-sale Securities \| Corporate
Schedule of Repurchase Agreements [Line Items]
Amortized Cost	1,965	2,923
Fair Value	1,580	3,208
Available-for-sale Securities \| U.S. government and agencies
Schedule of Repurchase Agreements [Line Items]
Amortized Cost	2,093	0
Fair Value	1,592	0
Available-for-sale Securities \| Collateralized Loan Obligations
Schedule of Repurchase Agreements [Line Items]
Amortized Cost	282	0
Fair Value	264	0
Available-for-sale Securities \| Foreign governments
Schedule of Repurchase Agreements [Line Items]
Amortized Cost	147	0
Fair Value	104	0
Available-for-sale Securities \| ABS
Schedule of Repurchase Agreements [Line Items]
Amortized Cost	1,207	0
Fair Value	$ 1,066	$ 0

Pledged Financial Instruments, Not Separately Reported, Securities for Repurchase Agreements, Fair Value

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- Definition

Pledged Financial Instruments, Not Separately Reported, Securities for Repurchase Agreements, Amortized Cost

+ References

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- Definition

[Line Items] for Schedule of Repurchase Agreements [Table]

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No definition available.

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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-URI https://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(2)(i)(A))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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-SubTopic 210
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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- Definition

Fair value of securities received as collateral against securities purchased under agreement to resell.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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