v3.26.1
Schedule H, Line 4i – Schedule of Assets (Held at End of Year)—Modified Cash Basis (Detail) - EBP 003 [Member] - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
EBP, Schedule of Asset Held for Investment [Line Items]    
Entity Tax Identification Number 55-0641179  
EBP, Plan Number 003  
EBP, Note Receivable from Participant $ 391,889 [1] $ 470,616
EBP, Asset Held for Investment $ 282,101,147  
Investment, Identifier [Axis]: American Beacon Small Cap Value R6 | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] American Beacon Small Cap Value R6 [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 56,104  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 1,311,158  
Investment, Identifier [Axis]: Fiam Core Plus Commingled Pool Class I | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Fiam Core Plus Commingled Pool Class I [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 245,360  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 6,067,763  
Investment, Identifier [Axis]: Galliard Stable Return Fund E | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Galliard Stable Return Fund E [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 301,067  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 19,077,264  
Investment, Identifier [Axis]: Great Gray Trust Europacific Growth CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Great Gray Trust Europacific Growth CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 465,204  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 7,300,213  
Investment, Identifier [Axis]: JP Morgan Large Cap Growth R6 | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] JP Morgan Large Cap Growth R6 [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 149,018  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 12,881,124  
Investment, Identifier [Axis]: MFS Large Cap Value CIT CL CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] MFS Large Cap Value CIT CL CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 610,705  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 8,503,333  
Investment, Identifier [Axis]: MFS Mid Cap Growth Fund CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] MFS Mid Cap Growth Fund CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 71,214  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 1,245,071  
Investment, Identifier [Axis]: MFS Mid Cap Value Fund CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] MFS Mid Cap Value Fund CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 31,499  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 724,462  
Investment, Identifier [Axis]: MassMutual Small Cap Gr Eq CIT Fee CI CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] MassMutual Small Cap Gr Eq CIT Fee CI CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 81,354  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 854,487  
Investment, Identifier [Axis]: NT Collective ACWI EX US IMI DC NL CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] NT Collective ACWI EX US IMI DC NL CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 25,623  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 3,256,912  
Investment, Identifier [Axis]: NT Collective AGG Bond NL Tier CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] NT Collective AGG Bond NL Tier CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 32,674  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 3,381,137  
Investment, Identifier [Axis]: NT Collective Extended Equity DC NL CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] NT Collective Extended Equity DC NL CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 154,358  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 20,921,633  
Investment, Identifier [Axis]: NT Collective S&P 500 DC NL Tier CT | units    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] NT Collective SP 500 DC NL Tier CT [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 366,302  
EBP, Investment, Current Value, Type [Extensible Enumeration] units [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 49,875,640  
Investment, Identifier [Axis]: United Bankshares, Inc. Common Stock | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] United Bankshares, Inc. Common Stock [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 1,773,917  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value [1] $ 68,118,408  
Investment, Identifier [Axis]: Vanguard Target Retirement 2020 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2020 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 97,491  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 2,676,125  
Investment, Identifier [Axis]: Vanguard Target Retirement 2025 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2025 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 423,109  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 8,441,016  
Investment, Identifier [Axis]: Vanguard Target Retirement 2030 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2030 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 372,640  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 15,773,839  
Investment, Identifier [Axis]: Vanguard Target Retirement 2035 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2035 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 493,896  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 13,522,881  
Investment, Identifier [Axis]: Vanguard Target Retirement 2040 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2040 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 230,984  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 11,537,655  
Investment, Identifier [Axis]: Vanguard Target Retirement 2045 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2045 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 219,265  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 7,617,271  
Investment, Identifier [Axis]: Vanguard Target Retirement 2050 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2050 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 164,137  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 9,730,053  
Investment, Identifier [Axis]: Vanguard Target Retirement 2055 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2055 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 52,573  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 3,478,241  
Investment, Identifier [Axis]: Vanguard Target Retirement 2060 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2060 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 40,695  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 2,481,564  
Investment, Identifier [Axis]: Vanguard Target Retirement 2065 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2065 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 28,722  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 1,149,751  
Investment, Identifier [Axis]: Vanguard Target Retirement 2070 Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement 2070 Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 4,095  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 130,316  
Investment, Identifier [Axis]: Vanguard Target Retirement Income Inv | shares    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Investment, Issuer Name [Extensible Enumeration] Vanguard Target Retirement Income Inv [Member]  
EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Participant-Directed [Member]  
EBP, Investment, Number of Shares 119,102  
EBP, Investment, Current Value, Type [Extensible Enumeration] shares [Member]  
EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value $ 1,651,941  
Minimum [Member]    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Asset Held for Investment, Participant Loan, Interest Rate 3.25%  
Maximum [Member]    
EBP, Schedule of Asset Held for Investment [Line Items]    
EBP, Asset Held for Investment, Participant Loan, Interest Rate 9.50%  
[1] Represents a party-in-interest to the Plan.