Loans and Allowances for Credit Losses Loans and Allowances for Credit Losses, Nonaccrual (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	$ 120,295	$ 121,797
Financing Receivable, Nonaccrual, No Allowance	98,545	90,854
Financing Receivable, Nonaccrual, With Allowance	21,750	30,943
Financing Receivable, Nonaccrual, Related Allowance	4,033	5,570
Commercial [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	54,432	60,297
Financing Receivable, Nonaccrual, No Allowance	46,722	45,531
Financing Receivable, Nonaccrual, With Allowance	7,710	14,766
Financing Receivable, Nonaccrual, Related Allowance	2,483	4,020
Commercial [Member] \| Energy [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	127	1,399
Financing Receivable, Nonaccrual, No Allowance	127	1,399
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Commercial [Member] \| Healthcare [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	37,247	41,034
Financing Receivable, Nonaccrual, No Allowance	37,247	34,661
Financing Receivable, Nonaccrual, With Allowance	0	6,373
Financing Receivable, Nonaccrual, Related Allowance	0	946
Commercial [Member] \| Services [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	8,097	16,228
Financing Receivable, Nonaccrual, No Allowance	387	7,835
Financing Receivable, Nonaccrual, With Allowance	7,710	8,393
Financing Receivable, Nonaccrual, Related Allowance	2,483	3,074
Commercial [Member] \| General business [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	8,961	1,636
Financing Receivable, Nonaccrual, No Allowance	8,961	1,636
Financing Receivable, Nonaccrual, With Allowance	0	0
Financing Receivable, Nonaccrual, Related Allowance	0	0
Commercial real estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	21,668	16,570
Financing Receivable, Nonaccrual, No Allowance	7,628	393
Financing Receivable, Nonaccrual, With Allowance	14,040	16,177
Financing Receivable, Nonaccrual, Related Allowance	1,550	1,550
Loans to individuals [Member]
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	44,195	44,930
Financing Receivable, Nonaccrual, No Allowance	44,195	44,930
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	29,693	29,791
Financing Receivable, Nonaccrual, No Allowance	29,693	29,791
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	200	134
Financing Receivable, Nonaccrual, No Allowance	200	134
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	14,302	15,005
Financing Receivable, Nonaccrual, No Allowance	14,302	15,005
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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+ References

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- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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