Credit Quality - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Minimum days for discontinue of accrual interest on commercial and consumer loan	90 days
Maximum days for discontinue of accrual interest on commercial and consumer loan	120 days
Minimum number of days required for special mention	30 days
Maximum number of days required for special mention	89 days
Number of days required for substandard	90 days
OREO	$ 2,670	$ 2,615
Recorded investment of consumer mortgage loans	$ 258	142
Description of Credit Risk Exposure	For United’s loans with a corporate credit exposure, United analyzes loans individually to classify the loans as to credit risk. Review and analysis of criticized (special mention-rated loans in the amount of $1,000 or greater) and classified (substandard-rated and worse in the amount of $500 and greater) loans is completed once per quarter. Review of notes with committed exposure of $2,000 or greater is completed at least annually.
Modification Additional Funds Recorded Investment	$ 718	$ 28