Loans and Allowance for Loan Losses (Schedule of Allowances for Loan Losses and Recorded Investment in Loans) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for loan losses:
Beginning balance	$ 457,010	$ 414,956	$ 443,424	$ 427,597
Charge-offs	(36,256)	(23,698)	(61,591)	(48,845)
Recoveries	9,860	7,133	16,645	13,671
Provision for (reversal of) loan losses	40,624	9,446	72,760	15,414
Ending balance	471,238	407,837	471,238	407,837
Commercial & Industrial
Allowance for loan losses:
Beginning balance	158,688	178,722	161,550	188,364
Charge-offs	(22,841)	(15,512)	(30,714)	(29,275)
Recoveries	6,402	3,208	9,878	5,571
Provision for (reversal of) loan losses	17,738	(6,410)	19,273	(4,652)
Ending balance	159,987	160,008	159,987	160,008
Commercial Real Estate
Allowance for loan losses:
Beginning balance	160,392	94,696	143,575	97,760
Charge-offs	(5)	(252)	(101)	(2,708)
Recoveries	378	572	662	933
Provision for (reversal of) loan losses	8,961	9,202	25,590	8,233
Ending balance	169,726	104,218	169,726	104,218
Total consumer
Allowance for loan losses:
Beginning balance	137,930	141,538	138,299	141,473
Charge-offs	(13,410)	(7,934)	(30,776)	(16,862)
Recoveries	3,080	3,353	6,105	7,167
Provision for (reversal of) loan losses	13,925	6,654	27,897	11,833
Ending balance	$ 141,525	$ 143,611	$ 141,525	$ 143,611

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
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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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
-Paragraph 13
-Subparagraph (e)
-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
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

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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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