| **General (Pre-Transition LFPB to Adjusted Opening Balance) (Details) - USD ($) $ in Millions** | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 |
|-------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Present value of future net premiums**                                                        |          |          |          |
| Effect of change in cash flow assumptions                                                       | $ 0           | $ 0           |          |
| Reclassification of reserves for policyholders on claim to Future policy benefits               |          |          |          |
| **Present value of future net premiums**                                                        |          |          |          |
| Effect of change in cash flow assumptions                                                       |          |          | $ 2,844       |
| De-recognition of shadow reserves                                                               |          |          |          |
| **Present value of future net premiums**                                                        |          |          |          |
| Effect of change in cash flow assumptions                                                       |          |          | (3,293)       |
| Re-measurement using an upper-medium grade fixed income instrument yield discount rate          |          |          |          |
| **Present value of future net premiums**                                                        |          |          |          |
| Effect of change in cash flow assumptions                                                       |          |          | 6,255         |
| Other adjustments                                                                               |          |          |          |
| **Present value of future net premiums**                                                        |          |          |          |
| Effect of change in cash flow assumptions                                                       |          |          | $ 8           |

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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of cumulative increase (decrease) in expected future policy benefit and expense component for liability of future policy benefit from cash flow assumption change for future cash flows.
+ References
Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29E -Publisher FASB -URI https://asc.fasb.org//1943274/2147480046/944-40-55-29EReference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480016/944-40-65-2Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 13I -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480046/944-40-55-13IReference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-6
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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