Credit Quality - Schedule of Amortized Cost Basis of Loan Modifications Made to Borrowers (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	$ 0	$ 5,162	$ 0	$ 5,341
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 3,466	$ 0	$ 3,466
% of Total Class of Financing Receivable	0.00%	0.09%	0.01%	0.12%
Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 8,082	$ 1,209	$ 15,352
Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	180	4,616	217	4,616
Commercial Real Estate [Member] \| Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 3,466	$ 0	$ 3,466
% of Total Class of Financing Receivable	0.00%	0.19%	0.06%	0.19%
Commercial Real Estate [Member] \| Owner-Occupied [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 422	$ 1,209	$ 422
Commercial Real Estate [Member] \| Owner-Occupied [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	0	0	37	0
Commercial Real Estate [Member] \| Nonowner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	5,162	0	5,341
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.19%	0.00%	0.20%
Commercial Real Estate [Member] \| Nonowner-Occupied [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 5,698	$ 0	$ 5,698
Commercial Real Estate [Member] \| Nonowner-Occupied [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	0	4,616	0	4,616
Other Commercial [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.05%	0.00%	0.25%
Other Commercial [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 1,962	$ 0	$ 9,232
Other Commercial [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	0	0	0	0
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.00%
Residential Real Estate [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 0	$ 0	$ 0
Residential Real Estate [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	180	0	180	0
Construction & Land Development [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.00%
Construction & Land Development [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 0	$ 0	$ 0
Construction & Land Development [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	0	0	0	0
Consumer [Member] \| Bankcard [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.00%
Consumer [Member] \| Bankcard [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 0	$ 0	$ 0
Consumer [Member] \| Bankcard [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	0	0	0	0
Consumer [Member] \| Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Amortized Cost Basis Loan Modification Term Extension And Interest Rate Reduction	0	0	0	0
Amortized Cost Basis Loan Modification Term Extension And Permanent Delay	$ 0	$ 0	$ 0	$ 0
% of Total Class of Financing Receivable	0.00%	0.00%	0.00%	0.00%
Consumer [Member] \| Other Consumer [Member] \| Term Extension [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 0	$ 0	$ 0
Consumer [Member] \| Other Consumer [Member] \| Other than insignificant payment delay [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modified	$ 0	$ 0	$ 0	$ 0

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