Investments (Investments in Fixed Maturity Securities Available-for-Sale by Sector) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
% of Total	100.00%	100.00%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 52	$ 31
Fixed maturity securities, available-for-sale	50,495	60,749
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	712	5,256
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	7,795	349
Available for Sale at Fair value - Amortized cost	$ 57,630	$ 55,873
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	64.60%	62.80%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 43	$ 26
Fixed maturity securities, available-for-sale	32,655	38,103
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	163	3,084
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5,758	194
Available for Sale at Fair value - Amortized cost	$ 38,293	$ 35,239
Canadian and Canadian provincial governments
Debt Securities, Available-for-sale [Line Items]
% of Total	7.10%	8.10%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	3,586	4,944
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	503	1,606
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	41	1
Available for Sale at Fair value - Amortized cost	$ 3,124	$ 3,339
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
% of Total	1.90%	1.70%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	953	1,050
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	4	37
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	105	7
Available for Sale at Fair value - Amortized cost	$ 1,054	$ 1,020
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
% of Total	7.40%	6.60%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 4	$ 0
Fixed maturity securities, available-for-sale	3,723	4,005
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6	22
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	444	41
Available for Sale at Fair value - Amortized cost	$ 4,165	$ 4,024
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	3.30%	3.00%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 1	$ 1
Fixed maturity securities, available-for-sale	1,670	1,849
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3	66
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	175	6
Available for Sale at Fair value - Amortized cost	$ 1,843	$ 1,790
US Treasury and Government [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	1.70%	3.50%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	863	2,105
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3	31
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	204	8
Available for Sale at Fair value - Amortized cost	$ 1,064	$ 2,082
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	2.20%	2.20%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	1,086	1,323
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	9	137
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	177	5
Available for Sale at Fair value - Amortized cost	$ 1,254	$ 1,191
Debt Security, Government, Non-US [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	11.80%	12.10%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 4	$ 4
Fixed maturity securities, available-for-sale	5,959	7,370
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	21	273
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	891	87
Available for Sale at Fair value - Amortized cost	$ 6,833	$ 7,188

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