Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 96,868	$ 87,161	$ 87,161
Charge-offs	6,683	2,293
Recoveries	4,101	982
Provision	4,089	6,158
Ending balance	98,375	92,008	96,868
Average balance	$ 7,759,005	$ 7,146,358
Net charge-offs to loan average balance (annualized)	0.13%	0.07%
Provision (benefit) for credit losses	$ 3,000	$ 6,200
Provision (benefit) for loan credit losses	4,089	6,158
Provision (release) for off-balance sheet commitments	(1,000)	(43)
Credit loss expense (benefit) for held to maturity securities	(39)	82
Real Estate \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	19,625	19,772	19,772
Charge-offs	455	42	42
Recoveries	30	60
Provision	(1,656)	891
Ending balance	17,544	20,681	19,625
Average balance	$ 2,438,476	$ 2,342,545
Net charge-offs to loan average balance (annualized)	0.07%	0.00%
Provision (benefit) for loan credit losses	$ (1,656)	$ 891
Real Estate \| Construction/ Land/ Land Development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,990	7,776	7,776
Charge-offs	0	0	0
Recoveries	0	0
Provision	(11)	289
Ending balance	9,979	8,065	9,990
Average balance	$ 1,130,355	$ 974,914
Net charge-offs to loan average balance (annualized)	0.00%	0.00%
Provision (benefit) for loan credit losses	$ (11)	$ 289
Real Estate \| Residential Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	10,619	8,230	8,230
Charge-offs	0	0	27
Recoveries	4	5
Provision	11	285
Ending balance	10,634	8,520	10,619
Average balance	$ 1,739,105	$ 1,519,325
Net charge-offs to loan average balance (annualized)	0.00%	0.00%
Provision (benefit) for loan credit losses	$ 11	$ 285
Commercial and Industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	55,330	50,148	50,148
Charge-offs	6,181	2,169	11,833
Recoveries	4,064	912
Provision	5,610	4,466
Ending balance	58,823	53,357	55,330
Average balance	$ 2,121,502	$ 2,070,356
Net charge-offs to loan average balance (annualized)	0.40%	0.25%
Provision (benefit) for loan credit losses	$ 5,610	$ 4,466
Mortgage Warehouse Lines of Credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	529	379	379
Charge-offs	0	0
Recoveries	0	0
Provision	132	186
Ending balance	661	565	529
Average balance	$ 306,248	$ 213,201
Net charge-offs to loan average balance (annualized)	0.00%	0.00%
Provision (benefit) for loan credit losses	$ 132	$ 186
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	775	856	856
Charge-offs	47	82	147
Recoveries	3	5
Provision	3	41
Ending balance	734	820	$ 775
Average balance	$ 23,319	$ 26,017
Net charge-offs to loan average balance (annualized)	0.76%	1.20%
Provision (benefit) for loan credit losses	$ 3	$ 41

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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- Definition

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

+ References

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

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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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

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- Definition

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

+ References

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
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)
-Publisher SEC

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.

+ References

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