Cover Page - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Jun. 30, 2026 |
Sep. 16, 2026 |
Dec. 31, 2025 |
|
| Cover [Abstract] | |||
| Document Type | 10-K | ||
| Amendment Flag | false | ||
| Entity Registrant Name | 5E ADVANCED MATERIALS, INC. | ||
| Entity Central Index Key | 0001888654 | ||
| Document Annual Report | true | ||
| Document Period End Date | Jun. 30, 2026 | ||
| Document Fiscal Year Focus | 2026 | ||
| Document Fiscal Period Focus | FY | ||
| Current Fiscal Year End Date | --06-30 | ||
| Document Transition Report | false | ||
| Entity File Number | 001-41279 | ||
| Entity Incorporation, State or Country Code | DE | ||
| Entity Tax Identification Number | 87-3426517 | ||
| Entity Address, Address Line One | 9329 Mariposa Road | ||
| Entity Address, Address Line Two | Suite 210 | ||
| Entity Address, City or Town | Hesperia | ||
| Entity Address, State or Province | CA | ||
| Entity Address, Postal Zip Code | 92344 | ||
| City Area Code | 442 | ||
| Local Phone Number | 221-0225 | ||
| Title of 12(b) Security | Common Stock, $0.01 par value | ||
| Trading Symbol | FEAM | ||
| Security Exchange Name | NASDAQ | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Filer Category | Non-accelerated Filer | ||
| Entity Small Business | true | ||
| Entity Emerging Growth Company | true | ||
| Entity Ex Transition Period | true | ||
| Entity Shell Company | false | ||
| ICFR Auditor Attestation Flag | false | ||
| Document Financial Statement Error Correction [Flag] | false | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Entity Public Float | $ 21.3 | ||
| Entity Common Stock, Shares Outstanding | 41,647,371 | ||
| Documents Incorporated by Reference [Text Block] | DOCUMENTS INCORPORATED BY REFERENCE Certain portions of the registrant's Definitive Proxy Statement relating to the 2026 Annual Meeting of Stockholders, to be filed with the Securities and Exchange Commission within 120 days after the end of the registrant’s fiscal year ended June 30, 2026, are incorporated by reference into Part III where indicated. |
||
| Auditor Name | PricewaterhouseCoopers LLP | ||
| Auditor Firm ID | 238 | ||
| Auditor Location | Denver, Colorado | ||
| Auditor Opinion [Text Block] | Opinion on the Financial Statements We have audited the accompanying consolidated balance sheets of 5E Advanced Materials, Inc. and its subsidiaries (the “Company”) as of June 30, 2026 and 2025, and the related consolidated statements of operations, of changes in stockholders’ equity and of cash flows for the years then ended, including the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of June 30, 2026 and 2025, and the results of its operations and its cash flows for the years then ended in conformity with accounting principles generally accepted in the United States of America. |