Loans and Allowance for Credit Losses, Loans by Portfolio Type (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	$ 6,432,171	$ 6,366,303
Loans, variable rate of interest	16,197,587	16,069,050
Loans, non-accrual	120,295	121,797
Total	22,750,053	22,557,150
Credit Commitments [Abstract]
Outstanding commitments to extend credit	15,100,000
Outstanding standby letters of credit	790,000
Commercial [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	3,427,345	3,392,422
Loans, variable rate of interest	10,735,572	10,759,780
Loans, non-accrual	54,432	60,297
Total	14,217,349	14,212,499
Commercial real estate [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	879,806	874,716
Loans, variable rate of interest	3,913,842	3,715,491
Loans, non-accrual	21,668	16,570
Total	4,815,316	4,606,777
Loans to individuals [Member]
Loan receivables disclosure [Abstract]
Loans, fixed rate of interest	2,125,020	2,099,165
Loans, variable rate of interest	1,548,173	1,593,779
Loans, non-accrual	44,195	44,930
Total	$ 3,717,388	$ 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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Period Type:	instant

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

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- Definition

Amount of loan with fixed rate of interest.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of loan with variable or adjustable rate of interest.

+ References

+ Details

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- Definition

Unused amount of commitments to extend credit to customers.

+ References

No definition available.

+ Details

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Period Type:	instant

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