Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Amortized cost, net	$ 49,649	$ 45,370
Equity securities, at fair value, cost	2,244	4,253
Amortized cost	$ 5,145	$ 4,174
Preferred stock, par or stated value per share (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	82,000	81,000
Preferred stock, shares outstanding (in shares)	82,000	81,000
Preferred Stock, liquidation preference	$ 2,050	$ 2,025
Common stock, par or stated value per share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	2,000,000,000	2,000,000,000
Common stock, shares, issued (in shares)	900,000,000	900,000,000
Common stock, shares, outstanding (in shares)	262,000,000	263,000,000
Treasury stock, shares (in shares)	638,000,000	637,000,000