Leases (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) branch	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) branch	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Leases [Abstract]
Number of branches | branch	413		413
Number of branches owned | branch	273		273
Number of branches leased | branch	140		140
ROU assets related to new leases			$ 1		$ 1
Operating lease income	$ 3	$ 3	7	$ 7
Sales-type or direct financing leases	339		339		$ 327
Sales-type or direct financing leases income	$ 3	$ 3	$ 6	$ 6
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets		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		Premises, equipment and software, net
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities		Other liabilities		Other liabilities
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term debt		Long-term debt		Long-term debt