Allowance for Credit Losses - Additional Information (Detail) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Losses [Line Items]
Reserve for lending-related commitments	$ 40,739	$ 40,739	$ 44,706
Maximum Period Related To Accrual Of Interest On Discontinued Loans		90 days
Accrued interest receivable net of allowance for credit loss	$ 110,042	$ 110,042	$ 111,420
Percentage of allowance for credit losses		1.39%
Financing receivable, allowance for credit loss, period increase (decrease)		$ 4,219
2024 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of projection for real GDP	2.10%
Percentage of unemployment rate	4.00%
2025 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of projection for real GDP	2.00%
Percentage of unemployment rate	4.20%		4.10%
2026 [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of projection for real GDP	2.00%
Percentage of unemployment rate	4.10%		4.00%
Accrued Income Receivable [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Accrued interest receivable net of allowance for credit loss	$ 91,330	$ 91,330	$ 88,963

Maximum period of time related to the accrual of interest on loans that have become past due.

No definition available.

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- Definition

Percentage of allowance for credit losses.

+ References

No definition available.

+ Details

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- Definition

Projection of the growth rate of the real gross domestic product (GDP) based on a direct comparison of the GDP from one year to the next.

+ References

No definition available.

+ Details

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- Definition

Percentage of unemployment rate.

+ References

No definition available.

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- Definition

Represents an accrued liability that is appropriate to cover estimated credit losses on off-balance sheet loan commitments, standby letters of credit, and guarantees.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-5

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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

+ Details

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11B

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