Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	$ 6,947,537	$ 6,739,706
Loans, variable rate of interest	17,265,347	17,328,293
Nonaccrual	79,327	46,725
Loans	24,292,211	24,114,724
Credit Commitments [Abstract]
Outstanding commitments to extend credit	14,700,000
Outstanding standby letters of credit	702,000
Commercial [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,445,595	3,450,238
Loans, variable rate of interest	10,898,430	11,565,251
Nonaccrual	40,157	14,647
Loans	14,384,182	15,030,136
Commercial real estate [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	684,294	668,532
Loans, variable rate of interest	4,830,222	4,380,015
Nonaccrual	6,925	9,905
Loans	5,521,441	5,058,452
Loans to individuals [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	2,817,648	2,620,936
Loans, variable rate of interest	1,536,695	1,383,027
Nonaccrual	32,245	22,173
Loans	$ 4,386,588	$ 4,026,136

-- None. No documentation exists for this element. --

No definition available.

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-7

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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount of loan with fixed rate of interest.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-3

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- Definition

Amount of loan with variable or adjustable rate of interest.

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- Definition

Unused amount of commitments to extend credit to customers.

+ References

No definition available.

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