Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	$ 7,318,742	$ 7,101,490
Loans, variable rate of interest	19,702,831	18,475,612
Nonaccrual	62,142	74,360
Total	27,083,715	25,651,462
Credit Commitments [Abstract]
Outstanding commitments to extend credit	16,600,000
Outstanding standby letters of credit	619,000
Commercial [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,648,332	3,494,944
Loans, variable rate of interest	12,619,958	11,750,021
Nonaccrual	29,158	36,102
Total	16,297,448	15,281,067
Commercial real estate [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	601,513	601,044
Loans, variable rate of interest	5,277,386	5,064,265
Nonaccrual	6,431	6,697
Total	5,885,330	5,672,006
Loans to individuals [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,068,897	3,005,502
Loans, variable rate of interest	1,805,487	1,661,326
Nonaccrual	26,553	31,561
Total	$ 4,900,937	$ 4,698,389

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- Definition

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

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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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- Definition

Unused amount of commitments to extend credit to customers.

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