Loans and ACL - Summary of Amortized Cost of TLMs (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2026 USD ($) Loan	Mar. 31, 2025 USD ($) Loan
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Total \| Loan	1	3
Amortized Cost, Total \| $	$ 251	$ 643
Interest Forgiveness [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Interest forgiveness \| Loan	0	1
Amortized Cost, Interest forgiveness \| $	$ 0	$ 141
Payment Deferral [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Payment Deferral \| Loan	1	2
Amortized Cost, Payment deferral \| $	$ 251	$ 502
Residential [Member] \| Interest Forgiveness [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Interest forgiveness \| Loan	0	1
Amortized Cost, Interest forgiveness \| $	$ 0	$ 141
Percentage of Amortized Cost to Gross Loans by Category, Interest forgiveness	0.00%	0.02%
Residential [Member] \| Payment Deferral [Member] \| Real Estate [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Payment Deferral \| Loan	1	1
Amortized Cost, Payment deferral \| $	$ 251	$ 493
Percentage of Amortized Cost to Gross Loans by Category, Payment deferral	0.04%	0.08%
Consumer [Member] \| Payment Deferral [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of Loans, Payment Deferral \| Loan	0	1
Amortized Cost, Payment deferral \| $	$ 0	$ 9
Percentage of Amortized Cost to Gross Loans by Category, Payment deferral	0.00%	0.03%

Financing receivable modified interest forgiveness number of loans.

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- Definition

Financing receivable modified number of loans.

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- Definition

Financing receivable modified payment deferral number of loans.

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- Definition

Modified interest forgiveness amortized cost.

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- Definition

Modified interest forgiveness, Percentage of amortized cost to gross loans by category.

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- Definition

Modified Payment Deferral Amortization Cost

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- Definition

Modified payment deferral amortized cost to gross loans by category.

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- Definition

Total modified loan amortized cost

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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.

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