Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	$ 6,966,562	$ 6,739,706
Loans, variable rate of interest	17,826,238	17,328,293
Nonaccrual	72,394	46,725
Total	24,865,194	24,114,724
Credit Commitments [Abstract]
Outstanding commitments to extend credit	15,300,000
Outstanding standby letters of credit	643,000
Commercial [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,400,985	3,450,238
Loans, variable rate of interest	11,079,685	11,565,251
Nonaccrual	32,270	14,647
Total	14,512,940	15,030,136
Commercial real estate [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	659,296	668,532
Loans, variable rate of interest	5,086,502	4,380,015
Nonaccrual	6,809	9,905
Total	5,752,607	5,058,452
Loans to individuals [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	2,906,281	2,620,936
Loans, variable rate of interest	1,660,051	1,383,027
Nonaccrual	33,315	22,173
Total	$ 4,599,647	$ 4,026,136

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

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

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- Definition

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

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- Definition

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

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Amount of loan with fixed rate of interest.

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Amount of loan with variable or adjustable rate of interest.

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- Definition

Unused amount of commitments to extend credit to customers.

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