Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Fixed maturities, amortized cost	$ 14,361	$ 12,979
Equity securities, cost	4,282	4,294
Land, building and equipment, accumulated depreciation	$ 337	$ 322
Common stock, par value	$ 2	$ 2
Common stock, shares authorized	500,000	500,000
Common stock, shares, issued	198,300	198,300
Treasury Stock, Shares	41,300	41,200