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Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis (Detail) - Level 3 [Member] - Nonrecurring [Member] - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Equity Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 8,342	$ 13,014
Collateral Dependent Loans [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	2,855	7,337
Repossessed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	644	614
Other Real Estate Owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 21,095	$ 32,868

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Fair value portion of asset recognized for present right to economic benefit.

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