Long -Term Borrowings - Schedule of Maturities of Long-term Borrowings (Detail) $ in Thousands	Sep. 30, 2025 USD ($)
Debt Disclosure [Abstract]
2025	$ 250,000
2026	0
2027	0
2028	0
2029 and thereafter	0
Total	$ 250,000

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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UNITED BANKSHARES INC/WV 10-Q