Allowance for Credit Losses (Summary of Activity In Allowance for Loan and Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Forecast period (years)	2 years
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 224,314	$ 225,141
Provision (credit)	(10,974)	28,355
Initial allowance on PCD loans		1,193
Charge-offs	(8,563)	(14,261)
Recoveries	5,874	6,755
Ending balance	210,651	209,259
Cumulative Effect, Period of Adoption, Adjustment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(37,924)
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		187,217
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	80,842	142,369
Provision (credit)	(3,922)	21,537
Initial allowance on PCD loans		0
Charge-offs	(3,331)	(5,369)
Recoveries	1,275	1,427
Ending balance	74,864	72,410
Commercial \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		(87,554)
Commercial \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		54,815
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	119,485	75,236
Provision (credit)	(5,504)	9,406
Initial allowance on PCD loans		0
Charge-offs	(4,469)	(7,769)
Recoveries	3,340	2,431
Ending balance	112,852	109,933
Consumer \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		30,629
Consumer \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		105,865
Unfunded Loan Commitment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,814	1,055
Provision (credit)	(1,243)	572
Ending balance	11,571	10,512
Unfunded Loan Commitment \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	8,885
Unfunded Loan Commitment \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,814	9,940
PCD Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	23,987	7,536
Provision (credit)	(1,548)	(2,588)
Initial allowance on PCD loans		1,193
Charge-offs	(763)	(1,123)
Recoveries	1,259	2,897
Ending balance	$ 22,935	26,916
PCD Loans \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		19,001
PCD Loans \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance		$ 26,537

Financing Receivable, Allowance For Credit Loss, Forecast Period

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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- Definition

Amount of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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