Loans and Allowance for Credit Losses - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2024
Allowance for loan losses
Beginning balance	$ 74,856	$ 73,462
Charge-offs	(1,305)	(2,939)
Recoveries	284	457
Provision (release)	2,383	5,238
Ending balance	76,218	76,218
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	5,213	6,413
Provision (credit)		(1,200)
Ending balance	5,213	5,213
Commercial and industrial
Allowance for loan losses
Beginning balance	33,821	32,244
Charge-offs	(743)	(1,529)
Recoveries	25	80
Provision (release)	524	2,832
Ending balance	33,627	33,627
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	1,008	954
Provision (credit)	(225)	(171)
Ending balance	783	783
Energy
Allowance for loan losses
Beginning balance	3,169	3,143
Recoveries		118
Provision (release)	156	64
Ending balance	3,325	3,325
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance		149
Provision (credit)	133	(16)
Ending balance	133	133
Commercial real estate - owner-occupied
Allowance for loan losses
Beginning balance	6,385	6,445
Provision (release)	306	246
Ending balance	6,691	6,691
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	89	125
Provision (credit)	18	(18)
Ending balance	107	107
Commercial real estate - non-owner-occupied
Allowance for loan losses
Beginning balance	27,989	28,130
Charge-offs	(549)	(1,397)
Provision (release)	1,642	2,349
Ending balance	29,082	29,082
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	4,020	5,096
Provision (credit)	99	(977)
Ending balance	4,119	4,119
Residential real estate
Allowance for loan losses
Beginning balance	3,466	3,456
Recoveries	259	259
Provision (release)	(302)	(292)
Ending balance	3,423	3,423
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	95	89
Provision (credit)	(28)	(22)
Ending balance	67	67
Consumer
Allowance for loan losses
Beginning balance	26	44
Charge-offs	(13)	(13)
Provision (release)	57	39
Ending balance	70	70
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	1
Provision (credit)	3	4
Ending balance	$ 4	$ 4

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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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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
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. 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 (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482454/460-10-45-1

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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