Investment Securities - Summary of Securities Available For Sale By Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	$ 173,093	$ 189,924
Fair value due in one year or less	47,657	24,488
Fair value due after one year through five years	59,047	66,250
Fair value	164,557	182,569
Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost due in one year or less	3,063
Amortized cost due after one year through five years	10,842
Amortized cost due after five years through ten years	39,888
Amortized cost due after ten years	2,361
Amortized cost	173,093
Fair value due in one year or less	3,064
Fair value due after one year through five years	10,668
Fair value due after five years through ten years	36,695
Fair value due after ten years	2,015
Fair value	164,557
Mortgage-backed securities - U.S. Government Sponsored Enterprises (GSEs) [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	116,939	132,040
Fair value due in one year or less	31,198	22,206
Fair value due after one year through five years	28,698	29,492
Fair value	$ 112,115	$ 127,647

Available for sale securities amortized cost and debt maturities fair value.

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