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Allowance for Credit Losses - Commercial real estate loan portfolio (Details) - Commercial real estate - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 6,261,871	$ 5,722,372
Percent of total of real estate securing the credit	100.00%	100.00%
Commercial real estate construction development
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 1,094,570	$ 1,313,984
Percent of total of real estate securing the credit	17.40%	23.00%
Hotel
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 1,063,914	$ 1,080,706
Percent of total of real estate securing the credit	17.00%	18.90%
Retail multi-tenant
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 722,207	$ 738,874
Percent of total of real estate securing the credit	11.50%	12.90%
Lot development: residential and commercial lots
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 612,017	$ 513,760
Percent of total of real estate securing the credit	9.80%	9.00%
Warehouse
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 443,213	$ 435,783
Percent of total of real estate securing the credit	7.10%	7.60%
Office/Professional buildings
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 511,359	$ 416,014
Percent of total of real estate securing the credit	8.20%	7.30%
1 - 4 family construction
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 385,380	$ 338,832
Percent of total of real estate securing the credit	6.20%	5.90%
Multi-family
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 622,232	$ 310,115
Percent of total of real estate securing the credit	9.90%	5.40%
Owner occupied real estate
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 353,540	$ 270,584
Percent of total of real estate securing the credit	5.60%	4.70%
Commercial leased properties
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 331,068	$ 194,023
Percent of total of real estate securing the credit	5.30%	3.40%
Farmland
Loan loss allowances, real estate securing credit
Amount of real estate securing the credit	$ 122,371	$ 109,697
Percent of total of real estate securing the credit	2.00%	1.90%

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- Definition

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+ References

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- Definition

Percentage of real estate that is collateral for financing receivable to total real estate collateral.

+ References

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: 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

Reference 3: 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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 5: 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 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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