Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 98,375	$ 92,008	$ 96,868	$ 87,161	$ 87,161
Charge-offs	3,706	2,751	10,389	5,044
Recoveries	760	832	4,861	1,814
Provision	5,436	4,264	9,525	10,422
Ending balance	100,865	94,353	100,865	94,353	96,868
Average balance	$ 7,926,058	$ 7,474,313	$ 7,842,531	$ 7,311,242
Net charge-offs to loan average balance (annualized)	0.15%	0.10%	0.14%	0.09%
Provision (benefit) for credit losses	$ 5,200	$ 4,300	$ 8,200	$ 10,500
Provision (benefit) for loan credit losses	5,436	4,264	9,525	10,422
Provision (release) for off-balance sheet commitments	(238)	88	(1,300)	45
Provision recovery for credit loss for held to maturity securities	32	46	(6)	36
Real Estate \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	17,544	20,681	19,625	19,772	19,772
Charge-offs	25	0	480	42	42
Recoveries	267	25	297	85
Provision	(542)	133	(2,198)	1,024
Ending balance	17,244	20,839	17,244	20,839	19,625
Average balance	$ 2,497,490	$ 2,406,625	$ 2,467,983	$ 2,374,762
Net charge-offs to loan average balance (annualized)	(0.04%)	0.00%	0.01%	0.00%
Provision (benefit) for loan credit losses	$ (542)	$ 133	$ (2,198)	$ 1,024
Real Estate \| Construction/ Land/ Land Development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,979	8,065	9,990	7,776	7,776
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision	(705)	664	(716)	953
Ending balance	9,274	8,729	9,274	8,729	9,990
Average balance	$ 1,058,972	$ 972,032	$ 1,094,664	$ 973,465
Net charge-offs to loan average balance (annualized)	0.00%	0.00%	0.00%	0.00%
Provision (benefit) for loan credit losses	$ (705)	$ 664	$ (716)	$ 953
Real Estate \| Residential Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	10,634	8,520	10,619	8,230	8,230
Charge-offs	0	27	0	27	27
Recoveries	4	5	8	10
Provision	1,142	520	1,153	805
Ending balance	11,780	9,018	11,780	9,018	10,619
Average balance	$ 1,787,829	$ 1,615,211	$ 1,763,467	$ 1,567,533
Net charge-offs to loan average balance (annualized)	0.00%	0.01%	0.00%	0.00%
Provision (benefit) for loan credit losses	$ 1,142	$ 520	$ 1,153	$ 805
Commercial and Industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	58,823	53,357	55,330	50,148	50,148
Charge-offs	3,668	2,714	9,849	4,883	11,833
Recoveries	484	800	4,548	1,712
Provision	5,545	2,730	11,155	7,196
Ending balance	61,184	54,173	61,184	54,173	55,330
Average balance	$ 2,128,486	$ 2,059,285	$ 2,124,994	$ 2,064,791
Net charge-offs to loan average balance (annualized)	0.60%	0.37%	0.50%	0.31%
Provision (benefit) for loan credit losses	$ 5,545	$ 2,730	$ 11,155	$ 7,196
Mortgage Warehouse Lines of Credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	661	565	529	379	379
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0
Provision	15	252	147	438
Ending balance	676	817	676	817	529
Average balance	$ 430,885	$ 396,348	$ 368,566	$ 305,280
Net charge-offs to loan average balance (annualized)	0.00%	0.00%	0.00%	0.00%
Provision (benefit) for loan credit losses	$ 15	$ 252	$ 147	$ 438
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	734	820	775	856	856
Charge-offs	13	10	60	92	147
Recoveries	5	2	8	7
Provision	(19)	(35)	(16)	6
Ending balance	707	777	707	777	$ 775
Average balance	$ 22,396	$ 24,812	$ 22,857	$ 25,411
Net charge-offs to loan average balance (annualized)	0.14%	0.13%	0.46%	0.67%
Provision (benefit) for loan credit losses	$ (19)	$ (35)	$ (16)	$ 6

Credit Loss, Expense (Reversal)

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- Definition

Percentage of writeoff after recovery to average financing receivables outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (4)
-Publisher SEC

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at amortized cost (held-to-maturity).

+ 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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- Definition

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

+ References

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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- Definition

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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- Definition

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

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-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.

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Average amount outstanding, before allowance for credit loss, of financing receivables.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph a
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Number 229
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (4)
-Publisher SEC

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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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