Loans and Allowance for Loan Losses (Schedule of Allowances for Loan Losses and Recorded Investment in Loans) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Allowance for loan losses:
Beginning balance	$ 443,424	$ 427,597
Charge-offs	(25,335)	(25,147)
Recoveries	6,785	6,538
Provision for (reversal of) loan losses	32,136	5,968
Ending balance	457,010	414,956
Commercial & Industrial
Allowance for loan losses:
Beginning balance	161,550	188,364
Charge-offs	(7,873)	(13,763)
Recoveries	3,476	2,363
Provision for (reversal of) loan losses	1,535	1,758
Ending balance	158,688	178,722
Commercial Real Estate
Allowance for loan losses:
Beginning balance	143,575	97,760
Charge-offs	(96)	(2,456)
Recoveries	284	361
Provision for (reversal of) loan losses	16,629	(969)
Ending balance	160,392	94,696
Total consumer
Allowance for loan losses:
Beginning balance	138,299	141,473
Charge-offs	(17,366)	(8,928)
Recoveries	3,025	3,814
Provision for (reversal of) loan losses	13,972	5,179
Ending balance	$ 137,930	$ 141,538

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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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.

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