Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 125,520	$ 125,520
Amortization of core deposit intangible assets	1,484	1,579	$ 1,296
Aggregate mortgage servicing rights (MSRs) amortization	343	330	350
Fair value of servicing rights	3,854	$ 3,018	2,689
Fair value of servicing rights, discount rate		12.00%
Mortgage loans	419,407	$ 442,635	456,149
Servicing fees	$ 1,085	$ 1,137	$ 1,063
Minimum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value of servicing rights, discount rate	5.30%
Fair value of servicing rights prepayment speed	13.94%	4.60%
Maximum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value of servicing rights, discount rate	10.40%
Fair value of servicing rights prepayment speed	7.30%	11.00%
Weighted Average [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value of servicing rights, discount rate	0.00%	0.00%
Fair value of servicing rights prepayment speed	10.83%
Average [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value of servicing rights, discount rate	6.96%

Mortgage loans.

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Servicing fees.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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