Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Loans and Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	$ 170,744		$ 170,744		$ 163,344
Additional funds committed to borrowers in TDR status	1,193		1,193		5,975
Specific reserves for TDRs included in the ACL on loans and leases:	574,325	$ 314,922	574,325	$ 314,922	301,187	$ 359,431
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the ACL on loans and leases:	516,315	269,171	516,315	269,171	257,877	312,244
Write-down	0	(1,100)	(10,000)	(3,000)
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the ACL on loans and leases:	58,010	45,751	58,010	45,751	43,310	$ 47,187
Write-down	(100)	$ 0	(200)	$ (300)
Performing Financial Instruments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	105,703		105,703		110,625
Nonperforming Financial Instruments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	65,041		65,041		52,719
Nonperforming Financial Instruments \| Troubled Debt Restructures \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the ACL on loans and leases:	7,274		7,274		9,017
Nonperforming Financial Instruments \| Troubled Debt Restructures \| Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the ACL on loans and leases:	$ 3,863		$ 3,863		$ 3,745