Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 91,060	$ 96,868	$ 96,868
Charge-offs	4,848	6,683
Recoveries	2,120	4,101
Provision	3,679	4,089
Ending balance	92,011	98,375	91,060
Average balance	$ 7,496,039	$ 7,759,005
Net charge-offs (recoveries) to loan average balance (annualized)	0.15%	0.13%
Provision for credit losses	$ 3,400	$ 3,000
Provision (release) for loan credit losses	3,679	4,089
Benefit for off-balance sheet commitments	233	1,000
Benefit for held to maturity securities	1	39
Real estate \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	16,546	19,625	19,625
Charge-offs	257	455	480
Recoveries	13	30
Provision	(117)	(1,656)
Ending balance	16,185	17,544	16,546
Average balance	$ 2,448,099	$ 2,438,476
Net charge-offs (recoveries) to loan average balance (annualized)	0.04%	0.07%
Provision (release) for loan credit losses	$ (117)	$ (1,656)
Real estate \| Construction/ Land/ Land Development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	7,398	9,990	9,990
Charge-offs	0	0	0
Recoveries	0	0
Provision	(562)	(11)
Ending balance	6,836	9,979	7,398
Average balance	$ 821,754	$ 1,130,355
Net charge-offs (recoveries) to loan average balance (annualized)	0.00%	0.00%
Provision (release) for loan credit losses	$ (562)	$ (11)
Real estate \| Residential Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,454	10,619	10,619
Charge-offs	0	0	11
Recoveries	46	4
Provision	527	11
Ending balance	13,027	10,634	12,454
Average balance	$ 1,909,922	$ 1,739,105
Net charge-offs (recoveries) to loan average balance (annualized)	(0.01%)	0.00%
Provision (release) for loan credit losses	$ 527	$ 11
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	53,449	55,330	55,330
Charge-offs	4,561	6,181	22,787
Recoveries	2,042	4,064
Provision	3,832	5,610
Ending balance	54,762	58,823	53,449
Average balance	$ 2,004,034	$ 2,121,502
Net charge-offs (recoveries) to loan average balance (annualized)	0.51%	0.40%
Provision (release) for loan credit losses	$ 3,832	$ 5,610
Mortgage Warehouse Lines of Credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	501	529	529
Charge-offs	0	0	0
Recoveries	0	0
Provision	(79)	132
Ending balance	422	661	501
Average balance	$ 289,521	$ 306,248
Net charge-offs (recoveries) to loan average balance (annualized)	0.00%	0.00%
Provision (release) for loan credit losses	$ (79)	$ 132
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	712	775	775
Charge-offs	30	47	362
Recoveries	19	3
Provision	78	3
Ending balance	779	734	$ 712
Average balance	$ 22,709	$ 23,319
Net charge-offs (recoveries) to loan average balance (annualized)	0.20%	0.76%
Provision (release) for loan credit losses	$ 78	$ 3

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
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-Paragraph b
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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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