Separate Accounts - Summary of Balances and Changes in Separate Account Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	$ 179,860	$ 168,438
Reinsurance Agreement | Protective
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	52	49
Variable Annuities
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	123,428	117,998	$ 120,470	$ 113,356
UL and Other
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	33,252	28,841	28,921	25,150
Retirement Plan Services
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	23,119	21,541	$ 22,033	$ 19,699
Other
Fair Value, Separate Account Investment [Line Items]
Separate account liabilities	$ 61	$ 58