Reserves in Addition to Account Balance, Based on Expected No-Lapse Guarantee Benefits and Expected Policy Assessments (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	$ 2,920	$ 3,015
Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	1,434	1,463
Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	1,486	1,552
Term Life Insurance | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	956	961
Whole Life Insurance | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	381	408
Long-Duration Insurance, Other | Life policy reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	97	94
Long-Duration Insurance, Other | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	107	111
Deferred Fixed Annuity | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	680	734
Universal life | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	575	578
Structured Settlement Annuity | Investment contract reserves:
Liability for Future Policy Benefit, by Product Segment
Life policy and investment contract reserves	$ 124	$ 129