Investments - Debt Securities with a Decline in Fair Value (Details) $ in Millions	Mar. 31, 2024 USD ($) position	Dec. 31, 2023 USD ($) position
Total
Total Fair Value, including held for sale assets	$ 6,577	$ 6,633
Total Amortized Cost, including held for sale assets	7,320	7,319
Total Unrealized Depreciation, including held for sale assets	$ (743)	$ (686)
Total Number of Issues, including held for sale assets \| position	2,413	2,353
Investment grade \| Debt securities
One year or less
Fair Value, including held for sale assets	$ 562	$ 330
Amortized Cost, including held for sale assets	576	338
Unrealized Depreciation, including held for sale assets	$ (14)	$ (8)
Number of Issues, including held for sale assets \| position	232	142
More than one year
Fair Value, including held for sale assets	$ 5,284	$ 5,441
Amortized Cost, including held for sale assets	5,946	6,036
Unrealized Depreciation, including held for sale assets	$ (662)	$ (595)
Number of Issues, including held for sale assets \| position	1,561	1,590
Below investment grade \| Debt securities
One year or less
Fair Value, including held for sale assets	$ 133	$ 161
Amortized Cost, including held for sale assets	137	170
Unrealized Depreciation, including held for sale assets	$ (4)	$ (9)
Number of Issues, including held for sale assets \| position	253	135
More than one year
Fair Value, including held for sale assets	$ 598	$ 701
Amortized Cost, including held for sale assets	661	775
Unrealized Depreciation, including held for sale assets	$ (63)	$ (74)
Number of Issues, including held for sale assets \| position	367	486

- Definition

Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Accumulated Loss Before Reclassification To Disposal Group Assets Held For Sale

+ References

No definition available.

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- Definition

Available For Sale Securities Continuous Unrealized Loss Position Less Than 12 Months Accumulated Loss Before Reclassification To Disposal Group Assets Held For Sale

+ References

No definition available.

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- Definition

Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Amortized Cost Before Reclassification To Disposal Group Assets Held For Sale

+ References

No definition available.

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- Definition

Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value Before Reclassification To Disposal Group Assets Held For Sale

+ References

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- Definition

Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Amortized Cost Before Reclassification To Disposal Group Assets Held For Sale

+ References

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- Definition

Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value Before Reclassification To Disposal Group Assets Held For Sale

+ References

No definition available.

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- Definition

Available For Sale Securities In Unrealized Loss Positions, Qualitative Disclosure, Less Than 12 Months, Number Of Positions, Before Reclassification To Disposal Group, Assets Held For Sale

+ References

No definition available.

+ Details

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- Definition

Available For Sale Securities In Unrealized Loss Positions, Qualitative Disclosure, Number Of Positions, Before Reclassification To Disposal Group, Assets Held For Sale

+ References

No definition available.

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- Definition

Available For Sale Securities In Unrealized Loss Positions, Qualitative Disclosure, Twelve Months Or Longer, Number Of Positions, Before Reclassification To Disposal Group, Assets Held For Sale

+ References

No definition available.

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- Definition

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months Or Longer

+ References

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- Definition

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less Than 12 Months

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- Definition

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- Definition

Debt Securities, Available-For-Sale, Unrealized Loss Position, Accumulated Loss, Before Reclassification To Disposal Group, Assets Held-For-Sale

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- Definition

Debt Securities, Available-For-Sale, Unrealized Loss Position, Amortized Cost, Before Reclassification To Disposal Group, Assets Held-For-Sale

+ References

No definition available.

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- Definition

Debt Securities, Available-For-Sale, Unrealized Loss Position, Before Reclassification To Disposal Group, Assets Held For Sale

+ References

No definition available.

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