Investments (Amortized Cost and Fair Value of Fixed Maturities by Contractual Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Available For Sale Securities Debt Maturities Amortized Cost
Due in one year or less	$ 1,511
Due after one year through five years	10,009
Due after five year through ten years	11,862
Due after ten years	27,740
Asset and mortgage-backed securities	6,727
Total	57,849	$ 55,873
Available For Sale Securities Debt Maturities Fair Value
Due in one year or less	1,517
Due after one year through five years	10,112
Due after five year through ten years	11,776
Due after ten years	28,019
Asset and mortgage-backed securities	6,498
Total	$ 57,922	$ 60,749

Amortized cost 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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