Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Fair Value, Fiscal Year Maturity [Abstract]
Fair Value	$ 10,809	$ 10,357
Fair Value Percent, Fiscal Year Maturity [Abstract]
Average life of ABS	3 years
Average life of MBS	5 years
Fixed maturities
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
One year or less	$ 923
After one year through five years	2,572
After five years through ten years	825
After ten years	351
Fixed maturities amortized cost, Subtotal	4,671
Collateralized loan obligations and other ABS (average life of approximately 3 years)	4,626
MBS (average life of approximately 5 years)	1,650
Amortized Cost	10,947
Fair Value, Fiscal Year Maturity [Abstract]
One year or less	930
After one year through five years	2,539
After five years through ten years	816
After ten years	342
Fixed maturities fair value, Subtotal	4,627
Collateralized loan obligations and other ABS (average life of approximately 3 years)	4,551
MBS (average life of approximately 5 years)	1,631
Fair Value	$ 10,809	$ 10,357
Fair Value Percent, Fiscal Year Maturity [Abstract]
One year or less	9.00%
After one year through five years	23.00%
After five years through ten years	8.00%
After ten years	3.00%
Fixed maturities fair value, Subtotal, Percent	43.00%
Collateralized loan obligations and other ABS (average life of approximately 3 years)	42.00%
MBS (average life of approximately 5 years)	15.00%
Fair value, Total, Percent	100.00%

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 excluding ABS and MBS fair value.

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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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Mortgage-backed securities, amortized cost.

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Mortgage-backed securities, fair value, percent.

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

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Collateralized loan obligations and Other asset-backed securities, amortized cost.

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Collateralized loan obligations and other Asset-backed securities, fair value.

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Collateralized loan obligations and other Asset-backed securities, fair value, percent.

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Mortgage backed securities average useful 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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Fair value 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 second through fifth 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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Fair value 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 second through fifth 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 after 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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Fair value 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 after 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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Fair value 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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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