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Allowance for Credit Losses (Collateral Dependent Loans and Leases) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	$ 37,637,013	$ 37,680,901
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	19,600,480	19,567,672
Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	6,189,992	6,278,154
Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	5,319,529	5,270,294
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	9,944,830	9,968,096
Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	5,352,598	5,537,618
Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2,950,782	2,769,643
Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	1,641,450	1,660,835
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	7,912,599	7,965,005
Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	5,829,833	5,933,352
Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2,082,766	2,031,653
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	70,570	84,104
Residential Real Estate | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	972	2,273
Residential Real Estate | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	67,495	79,440
Residential Real Estate | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2,103	2,391
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	27,904	37,671
Commercial Real Estate | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	14,507	13,116
Commercial Real Estate | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	9,347	20,198
Commercial Real Estate | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	1,341	2,856
Commercial Real Estate | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2,709	1,501
Commercial Real Estate | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Commercial Real Estate | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Commercial Real Estate | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	53,297	40,442
General Business Assets | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	13,988	15,800
General Business Assets | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	19,861	3,645
General Business Assets | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	19,448	20,997
General Business Assets | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	151,771	162,217
Total | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	14,507	13,116
Total | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	9,347	20,198
Total | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	16,301	20,929
Total | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	22,570	5,146
Total | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	19,448	20,997
Total | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	67,495	79,440
Total | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	$ 2,103	$ 2,391

X

- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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