Credit Quality and the Allowance for Loan and Lease Losses - Summary of Loans Modified in a TDR (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) loan	Sep. 30, 2022 USD ($) loan
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	2,093	7,381
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 77	$ 451
Increase (Decrease) to ALLL Upon Modification	2	22
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	19	69
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 31	$ 196
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	2	8
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 1	$ 5
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
Amortized Cost Basis in Loans Modified in a TDR During the Period		$ 23
Increase (Decrease) to ALLL Upon Modification		0
Charge-offs Recognized Upon Modification		$ 0
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan		2
Amortized Cost Basis in Loans Modified in a TDR During the Period		$ 4
Increase (Decrease) to ALLL Upon Modification		(3)
Charge-offs Recognized Upon Modification		$ 0
Residential Mortgage
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Period \| loan	190	928
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 28	$ 143
Increase (Decrease) to ALLL Upon Modification	0	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	54	178
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 3	$ 13
Increase (Decrease) to ALLL Upon Modification	(1)	(3)
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	448	2,499
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 7	$ 48
Increase (Decrease) to ALLL Upon Modification	0	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	1,380	3,694
Amortized Cost Basis in Loans Modified in a TDR During the Period	$ 7	$ 19
Increase (Decrease) to ALLL Upon Modification	3	8
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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