Investments (Investments in Fixed Maturity Securities Available-for-Sale by Sector) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 55	$ 31
Fixed maturity securities, available-for-sale	53,294	60,749
Available for Sale at Fair value - Amortized cost	57,608	$ 55,873
Funds Held Under Reinsurance Agreements Asset Specific Client	$ 4,100
Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	100.00%	100.00%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 55	$ 31
Fixed maturity securities, available-for-sale	53,294	60,749
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	870	5,256
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5,129	349
Available for Sale at Fair value - Amortized cost	$ 57,608	$ 55,873
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
% of Total	100.00%	100.00%
Fixed maturity securities, available-for-sale	$ 34,374	$ 38,103
Available for Sale at Fair value - Amortized cost	$ 37,819	$ 35,239
Corporate Debt Securities [Member] \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	64.50%	62.80%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 43	$ 26
Fixed maturity securities, available-for-sale	34,374	38,103
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	257	3,084
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3,659	194
Available for Sale at Fair value - Amortized cost	37,819	35,239
Canadian and Canadian provincial governments
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 3,809	$ 4,944
Canadian and Canadian provincial governments \| Fixed maturity securities
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	3,809	4,944
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	536	1,606
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	35	1
Available for Sale at Fair value - Amortized cost	3,308	3,339
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 950	$ 1,050
Residential mortgage-backed securities \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	1.80%	1.70%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	950	1,050
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	8	37
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	62	7
Available for Sale at Fair value - Amortized cost	1,004	1,020
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 3,782	$ 4,005
Asset-backed securities \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	7.10%	6.60%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 5	$ 0
Fixed maturity securities, available-for-sale	3,782	4,005
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3	22
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	307	41
Available for Sale at Fair value - Amortized cost	4,091	4,024
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 1,735	$ 1,849
Commercial Mortgage Backed Securities [Member] \| Fixed maturity securities
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	1,735	1,849
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2	66
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	122	6
Available for Sale at Fair value - Amortized cost	$ 1,856	$ 1,790
US Treasury and Government [Member] \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	1.80%	3.50%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	962	2,105
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	7	31
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	146	8
Available for Sale at Fair value - Amortized cost	1,101	2,082
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 1,116	$ 1,323
US States and Political Subdivisions Debt Securities [Member] \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	2.10%	2.20%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0	$ 0
Fixed maturity securities, available-for-sale	1,116	1,323
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	21	137
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	107	5
Available for Sale at Fair value - Amortized cost	1,202	1,191
Debt Security, Government, Non-US [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	$ 6,566	$ 7,370
Debt Security, Government, Non-US [Member] \| Fixed maturity securities
Debt Securities, Available-for-sale [Line Items]
% of Total	12.30%	12.10%
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 6	$ 4
Fixed maturity securities, available-for-sale	6,566	7,370
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	36	273
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	691	87
Available for Sale at Fair value - Amortized cost	$ 7,227	$ 7,188

Funds Withheld At Interest concentrated with one client.

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Percentage of available for sale securities

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