Loans and Leases and the Allowance for Credit Losses - Additional Information (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) payment	Dec. 31, 2024 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Accrued interest receivable	$ 69,224	$ 66,367
Revolving loans, converted to term loan during the period	$ 18,400	12,700
Threshold period for loans and leases to be past due	30 days
Number of missed payments to be considered delinquent \| payment	2
Consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure	$ 10,600	9,600
Pass \| Residential Mortgage
Accounts Notes And Loans Receivable [Line Items]
Number of days past due for loans and leases in classified credit quality indicator	90 days
Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)	60.00%
Pass \| Home Equity
Accounts Notes And Loans Receivable [Line Items]
Number of days past due for loans and leases in classified credit quality indicator	90 days
Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)	60.00%
Maximum current combined loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent)	60.00%
Accrued Interest Receivable
Accounts Notes And Loans Receivable [Line Items]
Accrued interest receivable	$ 48,300	$ 48,400
Consumer \| Classified
Accounts Notes And Loans Receivable [Line Items]
Number of days past due for loans and leases in classified credit quality indicator	90 days

Financing receivable credit quality current combined loan to value ratio percentage maximum.

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- Definition

Represents the maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass.

+ References

No definition available.

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- Definition

Financing receivable past due for loans and leases to be classified as classified credit quality indicator period.

+ References

No definition available.

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- Definition

Number Of Missed Payments To Be Considered Delinquent

+ References

No definition available.

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- 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/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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- Definition

Amount of increase in term loan from conversion of revolving financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6A

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- Definition

Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-14

+ Details

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477802/946-310-45-1

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 35
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-35

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