Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Common stock, par value (in dollars per share)	$ 5	$ 5
Common stock, authorized (shares)	800,000,000	800,000,000
Common stock, issued (shares)	543,225,979	543,116,271
Common stock held in treasury at cost (shares)	145,667,981	145,087,054
Other borrowed funds, fair value (less than)	$ 100.0	$ 100.0
Other liabilities	100.0	100.0
Preferred stock, par value	0.5	0.5
Fair Value
Loans held for sale, fair value	900.0	700.0
Loans, fair value	1,200.0	1,200.0
Other assets, fair value	$ 100.0	$ 100.0