Loans and Allowances for Credit Losses Loans and Allowances for Credit Losses, Nonaccrual (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	$ 119,515	$ 145,469
Financing Receivable, Nonaccrual, No Allowance	77,458	102,380
Financing Receivable, Nonaccrual, With Allowance	42,057	43,089
Financing Receivable, Nonaccrual, Related Allowance	2,960	2,692
Commercial [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	74,620	110,131
Financing Receivable, Nonaccrual, No Allowance	32,563	67,042
Financing Receivable, Nonaccrual, With Allowance	42,057	43,089
Financing Receivable, Nonaccrual, Related Allowance	2,960	2,692
Commercial [Member] \| Healthcare [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	49,307	81,529
Financing Receivable, Nonaccrual, No Allowance	9,668	40,372
Financing Receivable, Nonaccrual, With Allowance	39,639	41,157
Financing Receivable, Nonaccrual, Related Allowance	2,100	1,478
Commercial [Member] \| Services [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	3,319	3,616
Financing Receivable, Nonaccrual, No Allowance	1,542	1,684
Financing Receivable, Nonaccrual, With Allowance	1,777	1,932
Financing Receivable, Nonaccrual, Related Allowance	460	1,214
Commercial [Member] \| Energy [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	14,991	17,843
Financing Receivable, Nonaccrual, No Allowance	14,991	17,843
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Commercial [Member] \| General business [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	7,003	7,143
Financing Receivable, Nonaccrual, No Allowance	6,362	7,143
Financing Receivable, Nonaccrual, With Allowance	641	0
Financing Receivable, Nonaccrual, Related Allowance	400	0
Commercial real estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	22,087	7,320
Financing Receivable, Nonaccrual, No Allowance	22,087	7,320
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Loans to individuals [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	22,808	28,018
Financing Receivable, Nonaccrual, No Allowance	22,808	28,018
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Loans to individuals [Member] \| Residential mortgage [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	13,449	18,056
Financing Receivable, Nonaccrual, No Allowance	13,449	18,056
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Loans to individuals [Member] \| Personal [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	142	253
Financing Receivable, Nonaccrual, No Allowance	142	253
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
US Government Agency Insured Loans [Member] \| Loans to individuals [Member] \| Residential mortgage [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	9,217	9,709
Financing Receivable, Nonaccrual, No Allowance	9,217	9,709
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	$ 0	$ 0

Amount of financing receivable on nonaccrual status with a related allowance.

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- Definition

Amount of financing receivable on nonaccrual status with an allowance.

+ References

No definition available.

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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. 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 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

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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/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

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- Definition

Amortized cost of financing receivable on nonaccrual status. 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 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)
-Publisher SEC

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)
-Publisher SEC

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
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