Credit Quality and the Allowance for Loan and Lease Losses - Summary of Loans Modified in a TDR (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) loan	Jun. 30, 2022 USD ($) loan
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	2,546	5,288
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 197	$ 374
Increase (Decrease) to ALLL Upon Modification	4	20
Charge-offs Recognized Upon Modification	$ 0	$ 0
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	20	50
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 74	$ 165
Increase (Decrease) to ALLL Upon Modification	0	13
Charge-offs Recognized Upon Modification	$ 0	$ 0
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	1	6
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 0	$ 4
Increase (Decrease) to ALLL Upon Modification	0	(1)
Charge-offs Recognized Upon Modification	$ 0	$ 0
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	3	3
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 23	$ 23
Increase (Decrease) to ALLL Upon Modification	0	0
Charge-offs Recognized Upon Modification	$ 0	$ 0
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	2	2
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 4	$ 4
Increase (Decrease) to ALLL Upon Modification	(3)	(3)
Charge-offs Recognized Upon Modification	$ 0	$ 0
Residential Mortgage
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	478	738
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 73	$ 115
Increase (Decrease) to ALLL Upon Modification	4	7
Charge-offs Recognized Upon Modification	$ 0	$ 0
Consumer \| Home equity
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	72	124
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 3	$ 10
Increase (Decrease) to ALLL Upon Modification	(1)	(2)
Charge-offs Recognized Upon Modification	$ 0	$ 0
Consumer \| Indirect secured consumer loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	777	2,051
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 14	$ 41
Increase (Decrease) to ALLL Upon Modification	1	1
Charge-offs Recognized Upon Modification	$ 0	$ 0
Consumer \| Credit card
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	1,193	2,314
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 6	$ 12
Increase (Decrease) to ALLL Upon Modification	3	5
Charge-offs Recognized Upon Modification	$ 0	$ 0

Amount of credit loss expense (reversal of expense) on financing receivable from change in methodology. Excludes net investment in lease.

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