Fair Value of Assets and Liabilities - Change in unrealized gains and losses included in net income for level 3 assets and liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	$ 3	$ 37
Fair Value Recurring Basis Unobservable Input Reconciliation Liability Gain Loss Statement Of Income Extensible List Not Disclosed Flag			Total included in net income
Total included in net income	3	37
Total included in net income	3	37
Changes in unrealized net capital gains and losses reported in OCI	$ 1	$ (1)
Net investment income
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net investment income	Net investment income
Total included in net income	$ (5)	$ 9
Net gains (losses) on investments and derivatives
Gains (losses) included in net income for Level 3 assets and liabilities:
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net gains (losses) on investments and derivatives	Net gains (losses) on investments and derivatives
Total included in net income	$ 8	$ 28
Corporate - privately placed
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(4)	0
Changes in unrealized net capital gains and losses reported in OCI	0	1
Fixed income securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(4)	0
Equity securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(1)	25
Other investments
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	(1)	0
Other assets
Gains (losses) included in net income for Level 3 assets and liabilities:
Total recurring Level 3 assets	9	12
Corporate - public
Gains (losses) included in net income for Level 3 assets and liabilities:
Changes in unrealized net capital gains and losses reported in OCI	$ 1	$ (2)