Fair Value Measurements - Financial Instruments Not Carried At Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	$ 176,364	$ 158,888
Liabilities	174,211	155,703
Funds withheld liability	6,379	0
ACL on mortgage loans	12	17
Reported Value Measurement [Member] \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Funds withheld liability	6,379
Reported Value Measurement [Member] \| Level 3 \| Other policyholder funds and benefits payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	5,137	5,282
Reported Value Measurement [Member] \| Level 3 \| Policy loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	1,484	1,452
Reported Value Measurement [Member] \| Level 3 \| Mortgage loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	2,131	2,092
Estimate of Fair Value Measurement [Member] \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Funds withheld liability	6,379
Estimate of Fair Value Measurement [Member] \| Level 3 \| Other policyholder funds and benefits payable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	4,792	5,261
Estimate of Fair Value Measurement [Member] \| Level 3 \| Policy loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	1,484	1,452
Estimate of Fair Value Measurement [Member] \| Level 3 \| Mortgage loans
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	$ 2,138	$ 2,248

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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