Investments - Investments - Fixed Maturities, AFS, by Contractual Maturity Year (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Amortized Cost
One year or less	$ 1,541	$ 1,526
Over one year through five years	10,212	9,670
Over five years through ten years	6,440	6,568
Over ten years	9,824	9,370
Subtotal	28,017	27,134
Mortgage-backed and asset-backed securities	14,929	14,592
Fixed maturities, available-for-sale, at fair value, amortized cost	42,946	41,726
Fair Value
One year or less	1,517	1,501
Over one year through five years	9,900	9,433
Over five years through ten years	6,074	6,211
Over ten years	9,159	8,851
Subtotal	26,650	25,996
Mortgage-backed and asset-backed securities	14,190	13,822
Fixed maturities, available-for-sale, at fair value (amortized cost of $54,478 and $53,805)	$ 40,840	$ 39,818