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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
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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	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 62,781		$ 61,292
Allowance for loan and lease losses	(821)	$ (787)	(773)	$ (737)	$ (715)
Net loans and leases	61,960		60,519
Commercial: \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	30,518		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	1,300		1,200
Commercial: \| Loans to mortgage companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	2,934		2,024
Commercial: \| Commercial, financial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	33,452		32,633
Allowance for loan and lease losses	(344)	(348)		(326)	(325)
Commercial: \| Commercial, financial and industrial \| Paycheck Protection Plan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	19		29	44
Commercial: \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,669		14,216
Allowance for loan and lease losses	(221)	(181)		(159)	(150)
Commercial: \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	190		180
Consumer:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,909		13,650
Consumer: \| Home Equity Line of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	2,122		2,219
Consumer: \| Real estate installment loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	11,787		11,431
Consumer: \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	751		$ 793
Allowance for loan and lease losses	$ (25)	$ (27)		$ (31)	$ (31)