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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Loans and Leases - Schedule of Loans by Portfolio Segment (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 62,445		$ 61,292
Allowance for loan and lease losses	(823)	$ (821)	(773)	$ (760)	$ (737)	$ (685)
Net loans and leases	61,622		60,519
Commercial: \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	29,848		30,609
Commercial: \| Commercial and industrial \| Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Property, plant, and equipment and finance lease right-of-use asset	1,400		1,200
Commercial: \| Loans to mortgage companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	3,244		2,024
Commercial: \| Commercial, financial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	33,092		32,633
Allowance for loan and lease losses	(352)	(344)	(339)	(335)	(326)	(308)
Commercial: \| Commercial, financial and industrial \| Paycheck Protection Plan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	15		29	35
Commercial: \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,705		14,216
Allowance for loan and lease losses	(218)	(221)	(172)	(169)	(159)	(146)
Commercial: \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	184		180
Consumer:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,961		13,650
Consumer: \| Home Equity Line of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	2,085		2,219
Consumer: \| Real estate installment loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	11,876		11,431
Consumer: \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	687		793
Allowance for loan and lease losses	$ (23)	$ (25)	$ (29)	$ (28)	$ (31)	$ (31)