Loans and Allowance for Credit Losses - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2023
Allowance for loan losses
Beginning balance	$ 65,130	$ 61,775
Charge-offs	(743)	(2,385)
Recoveries	140	141
Provision (release)	3,040	8,036
Ending balance	67,567	67,567
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	8,113	8,688
Provision (credit)	(400)	(975)
Ending balance	7,713	7,713
Commercial And Industrial [Member]
Allowance for loan losses
Beginning balance	27,660	26,803
Charge-offs	(738)	(2,380)
Recoveries	3	4
Provision (release)	2,004	4,502
Ending balance	28,929	28,929
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	461	319
Provision (credit)	(12)	130
Ending balance	449	449
Energy [Member]
Allowance for loan losses
Beginning balance	4,679	4,396
Charge-offs	0	0
Recoveries	137	137
Provision (release)	98	381
Ending balance	4,914	4,914
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	541	787
Provision (credit)	(45)	(291)
Ending balance	496	496
Commercial Real Estate - Owner-Occupied [Member]
Allowance for loan losses
Beginning balance	5,610	5,214
Charge-offs	0	0
Recoveries	0	0
Provision (release)	751	1,147
Ending balance	6,361	6,361
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	226	221
Provision (credit)	(21)	(16)
Ending balance	205	205
Commercial Real Estate - Non-Owner-Occupied [Member]
Allowance for loan losses
Beginning balance	23,807	21,880
Charge-offs	0	0
Recoveries	0	0
Provision (release)	174	2,101
Ending balance	23,981	23,981
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	6,819	7,323
Provision (credit)	(323)	(827)
Ending balance	6,496	6,496
Residential Real Estate [Member]
Allowance for loan losses
Beginning balance	3,265	3,333
Charge-offs	0	0
Recoveries	0	0
Provision (release)	3	(65)
Ending balance	3,268	3,268
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	59	35
Provision (credit)	8	32
Ending balance	67	67
Consumer [Member]
Allowance for loan losses
Beginning balance	109	149
Charge-offs	(5)	(5)
Recoveries	0	0
Provision (release)	10	(30)
Ending balance	114	114
Allowance for Credit Losses on Off-Balance Sheet
Beginning balance	7	3
Provision (credit)	(7)	(3)
Ending balance	$ 0	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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.

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