Leases (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) branch	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Leases [Abstract]
Number of branches | branch	408
Number of branches owned | branch	278
Number of branches leased | branch	130
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets		Other assets
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Premises, equipment and software, net		Premises, equipment and software, net
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities		Other liabilities
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term debt		Long-term debt
Operating lease income | $	$ 3	$ 3
Sales-type or direct financing leases | $	388		$ 383
Sales-type or direct financing leases income | $	$ 4	$ 4