Capital Structure (Details) - USD ($)	Apr. 17, 2023	Mar. 31, 2023	Mar. 29, 2023	Dec. 31, 2022
Debt outstanding:
Preferred stock, par value (in dollars per share)		$ 1		$ 1
Subsequent Event
Debt outstanding:
Redemption of preferred stock	$ 575,000,000
Series G Noncumulative Preferred Stock | Subsequent Event
Debt outstanding:
Stock redeemed (in shares)	23,000
Preferred stock, par value (in dollars per share)	$ 1.00
Liquidation preference amount (in dollars per shares)	$ 25,000
Senior Notes
Debt outstanding:
Repayments of debt		$ 250,000,000	$ 250,000,000
Senior Notes | Senior Notes Due 2033 at 5.25 Percent
Debt outstanding:
Issuance of debt		$ 750,000,000
Interest rate		5.25%
Senior Notes | London Interbank Offered Rate (LIBOR)
Debt outstanding:
Bear interest at floating rate			0.63%