Other Insurance Liabilities and Separate Accounts - Separate Account Assets (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	$ 3,311	$ 3,250
Separate accounts liabilities	3,311	3,250	$ 3,228
Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	3,499	3,204
Other Payables | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts liabilities	188
Other Receivables | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets		46
Cash and cash equivalents | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	165	168
Debt securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	856	2,507
Debt securities | U.S. government securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	186	573
Debt securities | States, municipalities and political subdivisions | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	14	28
Debt securities | U.S. corporate securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	524	1,632
Debt securities | Foreign securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	51	202
Mortgage-backed securities | Residential mortgage-backed securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	71	51
Mortgage-backed securities | Commercial mortgage-backed securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	3	6
Other asset-backed securities | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	7	15
Common/collective trusts | Recurring
Fair Value, Separate Account Investment [Line Items]
Separate accounts assets	$ 2,478	$ 529