Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	$ 6,614,145	$ 6,366,303
Loans, variable rate of interest	16,990,288	16,069,050
Loans, non-accrual	119,585	121,797
Total	23,724,018	22,557,150
Credit Commitments [Abstract]
Outstanding commitments to extend credit	14,400,000
Outstanding standby letters of credit	760,000
Commercial [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,536,353	3,392,422
Loans, variable rate of interest	11,112,788	10,759,780
Loans, non-accrual	70,698	60,297
Total	14,719,839	14,212,499
Commercial real estate [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	848,042	874,716
Loans, variable rate of interest	4,385,840	3,715,491
Loans, non-accrual	7,418	16,570
Total	5,241,300	4,606,777
Loans to individuals [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	2,229,750	2,099,165
Loans, variable rate of interest	1,491,660	1,593,779
Loans, non-accrual	41,469	44,930
Total	$ 3,762,879	$ 3,737,874

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

No definition available.

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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.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481990/310-10-45-2

+ Details

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

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

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- Definition

Amount of loan with fixed rate of interest.

+ References

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- Definition

Amount of loan with variable or adjustable rate of interest.

+ References

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- Definition

Unused amount of commitments to extend credit to customers.

+ References

No definition available.

+ Details

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