Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Tax provision at U.S. federal statutory rate	$ 191	$ 137
Nontaxable investment income	(11)	(11)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	(12)	(3)
Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Amount	(16)	(9)
Other	(6)	(4)
Income tax expense	$ 158	$ 118