Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Fair Value, Fiscal Year Maturity [Abstract]
Available for sale (AFS) fixed maturities	$ 11,052	$ 10,398
Fair Value Percent, Fiscal Year Maturity [Abstract]
Collateralized loan obligations and other asset-backed securities average life	3 years 6 months
Average life of Residential MBS	6 years
Fixed maturities
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
One year or less	$ 629
After one year through five years	2,320
After five years through ten years	1,395
After ten years	233
Fixed maturities amortized cost, Subtotal	4,577
Amortized cost	11,080
Fair Value, Fiscal Year Maturity [Abstract]
One year or less	626
After one year through five years	2,342
After five years through ten years	1,432
After ten years	220
Fixed maturities fair value, Subtotal	4,620
Available for sale (AFS) fixed maturities	$ 11,052	$ 10,398
Fair Value Percent, Fiscal Year Maturity [Abstract]
One year or less	6.00%
After one year through five years	21.00%
After five years through ten years	13.00%
After ten years	2.00%
Fixed maturities fair value, Subtotal, Percent	42.00%
Total, percent of fair value	100.00%
Collateralized loan obligations and other asset backed securities
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date	$ 3,696
Fair Value, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date	$ 3,685
Fair Value Percent, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date, percent of fair value	33.00%
Mortgage-backed securities
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date	$ 2,807
Fair Value, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date	$ 2,747
Fair Value Percent, Fiscal Year Maturity [Abstract]
Fixed maturities without a single maturity date, percent of fair value	25.00%

Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value, Percent.

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Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value, Percent.

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Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value, Percent.

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Available for sale securities debt maturities excluding ABS and MBS amortized cost.

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Available-for-sale Securities, Debt Maturities, Fair Value, Total, Percent.

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Available For Sale Securities, Debt Maturities, Fair Value Percent, Fiscal Year Maturity [Abstract]

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Available-for-sale Securities, Debt Maturities, within One Year, Fair Value, Percent.

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Collateralized loan obligations and Other asset-backed securities average life.

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Mortgage backed securities average life.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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