Document And Entity Information - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Mar. 06, 2026 |
Jun. 30, 2025 |
|
| Cover [Abstract] | |||
| Entity Registrant Name | FIRST US BANCSHARES, INC | ||
| Document Type | 10-K | ||
| Trading Symbol | FUSB | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Common Stock, Shares Outstanding | 5,650,157 | ||
| Entity Central Index Key | 0000717806 | ||
| Entity Filer Category | Non-accelerated Filer | ||
| Document Period End Date | Dec. 31, 2025 | ||
| Document Fiscal Year Focus | 2025 | ||
| Document Fiscal Period Focus | FY | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Shell Company | false | ||
| Entity Small Business | true | ||
| Entity Emerging Growth Company | false | ||
| Security Exchange Name | NASDAQ | ||
| Entity File Number | 000-14549 | ||
| Entity Incorporation, State or Country Code | DE | ||
| Entity Tax Identification Number | 63-0843362 | ||
| Entity Address, Address Line One | 3291 U.S. Highway 280 | ||
| Entity Address, City or Town | Birmingham | ||
| Entity Address, State or Province | AL | ||
| Entity Address, Postal Zip Code | 35243 | ||
| City Area Code | 205 | ||
| Local Phone Number | 582-1200 | ||
| Document Annual Report | true | ||
| Document Transition Report | false | ||
| ICFR Auditor Attestation Flag | false | ||
| Title of 12(b) Security | Common Stock, par value $0.01 per share | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Document Financial Statement Error Correction [Flag] | false | ||
| Entity Public Float | $ 67,949,382 | ||
| Amendment Flag | false | ||
| Auditor Firm ID | 213 | ||
| Auditor Name | Carr, Riggs & Ingram, LLC | ||
| Auditor Location | Atlanta, Georgia, United States | ||
| Documents Incorporated by Reference | DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant’s definitive proxy statement for the 2026 Annual Meeting of Shareholders to be held on April 30, 2026 are incorporated by reference into Part III of this Annual Report on Form 10-K. |
||
| Auditor Opinion [Text Block] | Opinion on the Financial Statements
We have audited the accompanying consolidated balance sheets of First US Bancshares, Inc. and subsidiary (the "Company") as of December 31, 2025 and 2024, the related consolidated statements of operations, comprehensive income, changes in shareholders’ equity, and cash flows for each of the two years in the period ended December 31, 2025, and the related notes (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the consolidated financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America. |