Cover
| Cover | Sep. 29, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Sep. 29, 2022 |
| Entity File Number | 0-16540 |
| Entity Registrant Name | UNITED BANCORP, INC. |
| Entity Central Index Key | 0000731653 |
| Entity Tax Identification Number | 34-1405357 |
| Entity Incorporation, State or Country Code | OH |
| Entity Address, Address Line One | 201 South 4th Street |
| Entity Address, City or Town | Martins Ferry |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 43935-0010 |
| City Area Code | 740 |
| Local Phone Number | 633-0445 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, Par Value $1.00 |
| Trading Symbol | UBCP |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |