Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 99,015	$ 92,011	$ 96,782	$ 91,060	$ 91,060
Charge-offs	2,496	3,700	6,459	8,548
Recoveries	2,042	1,400	3,228	3,520
Provision	(373)	2,715	4,637	6,394
Ending balance	98,188	92,426	98,188	92,426	96,782
Average balance	$ 7,954,669	$ 7,673,268	$ 7,795,969	$ 7,585,143
Net charge-offs (recoveries) to loan average balance (annualized)	0.02%	0.12%	0.08%	0.13%
Provision for credit losses	$ 65	$ 2,900	$ 5,000	$ 6,300
Net (benefit) provision for loan credit losses	(373)	2,715	4,637	6,394
Net (benefit) provision for off-balance sheet commitments	440	149	395	(84)
Net (benefit) provision for held to maturity securities	(2)	(2)	(3)	(3)
Real estate \| Commercial Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	19,388	16,185	18,929	16,546	16,546
Charge-offs	449	471	1,224	728	728
Recoveries	1	0	1	13
Provision	138	1,071	1,372	954
Ending balance	19,078	16,785	19,078	16,785	18,929
Average balance	$ 2,563,643	$ 2,407,632	$ 2,535,076	$ 2,427,754
Net charge-offs (recoveries) to loan average balance (annualized)	0.07%	0.08%	0.10%	0.06%
Net (benefit) provision for loan credit losses	$ 138	$ 1,071	$ 1,372	$ 954
Real estate \| Construction/ Land/ Land Development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	6,996	6,836	7,219	7,398	7,398
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(431)	(512)	(654)	(1,074)
Ending balance	6,565	6,324	6,565	6,324	7,219
Average balance	$ 675,151	$ 739,601	$ 651,871	$ 780,450
Net charge-offs (recoveries) to loan average balance (annualized)	0.00%	0.00%	0.00%	0.00%
Net (benefit) provision for loan credit losses	$ (431)	$ (512)	$ (654)	$ (1,074)
Real estate \| Residential real estate \| Single-family residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	9,793	8,949	9,525	8,623	8,623
Charge-offs	277	119	309	119	489
Recoveries	0	7	2	10
Provision	474	222	772	545
Ending balance	9,990	9,059	9,990	9,059	9,525
Average balance	$ 1,428,511	$ 1,462,025	$ 1,438,587	$ 1,450,386
Net charge-offs (recoveries) to loan average balance (annualized)	0.08%	0.03%	0.04%	0.02%
Net (benefit) provision for loan credit losses	$ 474	$ 222	$ 772	$ 545
Real estate \| Residential real estate \| Multifamily residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	6,811	4,078	4,963	3,831	3,831
Charge-offs	0	0	0	0
Recoveries	0	0	0	43
Provision	(150)	502	1,698	706
Ending balance	6,661	4,580	6,661	4,580	4,963
Average balance	$ 572,052	$ 493,397	$ 560,826	$ 482,412
Net charge-offs (recoveries) to loan average balance (annualized)	0.00%	0.00%	0.00%	(0.02%)
Net (benefit) provision for loan credit losses	$ (150)	$ 502	$ 1,698	$ 706
Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	54,427	54,762	54,496	53,449	53,449
Charge-offs	1,716	2,995	4,720	7,556	43,691
Recoveries	1,935	1,390	3,117	3,432
Provision	(412)	1,018	1,341	4,850
Ending balance	54,234	54,175	54,234	54,175	54,496
Average balance	$ 2,212,814	$ 2,068,175	$ 2,145,200	$ 2,036,281
Net charge-offs (recoveries) to loan average balance (annualized)	(0.04%)	0.31%	0.15%	0.41%
Net (benefit) provision for loan credit losses	$ (412)	$ 1,018	$ 1,341	$ 4,850
Mortgage Warehouse Lines of Credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	998	422	913	501	501
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	69	358	154	279
Ending balance	1,067	780	1,067	780	913
Average balance	$ 483,340	$ 480,587	$ 444,920	$ 385,582
Net charge-offs (recoveries) to loan average balance (annualized)	0.00%	0.00%	0.00%	0.00%
Net (benefit) provision for loan credit losses	$ 69	$ 358	$ 154	$ 279
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	602	779	737	712	712
Charge-offs	54	115	206	145	174
Recoveries	106	3	108	22
Provision	(61)	56	(46)	134
Ending balance	593	723	593	723	$ 737
Average balance	$ 19,158	$ 21,851	$ 19,489	$ 22,278
Net charge-offs (recoveries) to loan average balance (annualized)	(1.09%)	2.06%	1.01%	1.11%
Net (benefit) provision for loan credit losses	$ (61)	$ 56	$ (46)	$ 134

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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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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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/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
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-Publisher FASB
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-Topic 326
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-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 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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- 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
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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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