| Description of Company and Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
| Jun. 30, 2022 |
| Policy Text Block [Abstract] | |
| Nature of Business | Nature of Business 5E Advanced Materials, Inc. (“5E,” “we,” “our,” or “us” or the “Company”) is an exploration stage company focused on becoming a vertically integrated global leader in boron specialty advanced materials and lithium with a focus on enabling decarbonization. |
| Reorganization | Reorganization 5E Advanced Materials, Inc. acquired all of the issued and outstanding shares of American Pacific Borates Limited (“ABR”), our Australian predecessor and wholly owned subsidiary, pursuant to a Scheme of Arrangement (“Scheme”) under Australian law, which was approved by ABR’s shareholders on December 2, 2021, and the Supreme Court of Western Australia on February 24, 2022. As part of the Scheme, we changed our place of domicile from Australia to the State of Delaware in the United States, effective on March 8, 2022. In accordance with the Scheme, all ordinary shares of ABR have been transferred to us and pursuant to the Scheme, we issued to the shareholders of ABR, either one share of our common stock for every ten ordinary shares of ABR or one CHESS Depository Interest (“CDIs”) over our common stock for every one ordinary share of ABR, in each case, as held on the Scheme record date. We maintain an Australian Stock Exchange (“ASX”) listing for our CDIs, with each CDI representing 1/10th of a share of common stock. Holders of CDIs are able to trade their CDIs on the ASX under the symbol “5EA” and holders of shares of our common stock are able to trade their shares on NASDAQ |
| Basis of Presentation | Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The financial statements are presented in U.S. dollars. |
| Basis of Consolidation | Basis of Consolidation The consolidated financial statements comprise the financial statements of 5E and its wholly owned subsidiaries, ABR, Fort Cady Holdings Pty Ltd, and Fort Cady (California) Corporation (“FCCC”). In preparing the consolidated financial statements, all intercompany balances and transactions, income and expenses and profit and losses resulting from intra-company transactions have been eliminated in full. |
| Concentration of Risk | Concentration of Risk We maintain cash deposits at several major banks, which at times may exceed amounts covered by insurance provided by the United States Federal Deposit Insurance Corporation (“FDIC”). We monitor the financial health of the banks and have not experienced any losses in such accounts and believe we are not exposed to any significant credit risk. |
| Risk and Uncertainties | Risk and Uncertainties We are subject to a number of risks similar to those of other companies of similar size in our industry, including but not limited to, the success of our exploration activities, need for significant additional capital (or financing) to fund operating losses, competition from substitute products and services from larger companies, protection of proprietary technology, patent litigation, and dependence on key individuals. |
| Use of Estimates | Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates, assumptions, and allocations that affect amounts reported in the consolidated financial statements and related notes. Items that are subject to such estimates and assumptions include, but are not limited to, estimated useful lives and valuation of properties, plant and equipment, mineral rights and properties, deferred tax assets, estimation of future costs, useful life, and discount rates used to calculate our reclamation liabilities, and fair value of stock-based compensation. Actual results could differ due to the uncertainty inherent in the nature of these estimates. |
| Foreign Currency Translation | Foreign Currency Translation Functional and reporting currency— rate During the fourth quarter ended June 30, 2022, ABR transferred substantially all of its assets to us and has no ongoing operations. Accordingly, we recognized the remaining accumulated foreign currency translation adjustment of thousand as a gain in our consolidated statement of operations and comprehensive income (loss). Transactions in foreign currency— and non-monetary assets Translation to reporting currency—
• Assets and liabilities for each statement of financial position presented are translated at the closing rate at the end of the reporting date;
• Income and expenses for each statement of operations are translated at average exchange rates, unless this average is not a reasonable approximation of the cumulative effect of the rates prevailing on the transaction dates, in which case income and expenses are translated at the rate on the dates of the transactions; and
• All resulting exchange differences are recognized in other comprehensive income or loss. |
| Cash and Cash Equivalents | Cash and Cash Equivalents — ctiv |
| Mineral Rights and Properties and Exploration and Evaluation Costs | Mineral Rights and Properties and Exploration and Evaluation Costs — Exploration and evaluation costs are classified as project expenses and expensed as incurred. When it is determined that a mining deposit can be economically and legally extracted or produced, development costs related to such reserves and incurred after such determination will be considered for capitalization. The establishment of proven and probable reserves is based on results of feasibility studies. Upon commencement of commercial production, capitalized costs will be amortized over their estimated useful lives or units of production, whichever is a more reliable measure. Capitalized amounts relating to a property that is abandoned or otherwise considered uneconomic for the foreseeable future will be written off. Drilling, development and related costs are either classified as project expenses and charged to operations as incurred, or capitalized, based on the following criteria:
• whether the drilling or development costs relate to a project that has been determined to be economically feasible, and a decision has been made to put the project into production; and
• whether, at the time the cost is incurred: (a) the expenditure embodies a probable future benefit that involves a capacity, singly or in combination with other assets, to contribute directly or indirectly to future net cash inflows, (b) we can obtain the benefit and control others’ access to it, and (c) the transaction or event giving rise to our right to or control of the benefit has already occurred. |
| Impairment of Long-Lived Assets | Impairment of Long-Lived Assets — ws |
| Properties, Plant and Equipment | Properties, Plant and Equipment— Assets under construction (“Construction in progress”) include roads, fencing, tailings facility, equipment for our small-scale boron facility, injection-recovery wells, and land improvements and will be depreciated in accordance with our depreciation policy once placed in service. |
| Reclamation Liabilities | Reclamation Liabilities — reclaimed on an ongoing basis. Reclamation associated with environmental monitoring programs will be classified as a long-term liability; however, because we have not declared proven and probable reserves, the timing of these reclamation activities is uncertain as the reclamation areas will only be utilized once the mineral property is operating. For activities that do not qualify for asset capitalization, the costs associated with the obligation are charged to operations. For other activities, the costs will be added to the capitalized costs of the property and amortized over the useful life of the mineral property. The reclamation obligation in connection with mineral properties and interests are reviewed on an annual basis unless otherwise deemed necessary. Environmental compliance costs related to maintaining our existing permits are expensed in the period incurred. Reclamation obligations are secured by certificate of deposits held for the benefit of the state of California in amounts determined by applicable federal and state regulatory agencies. Reclamation bond deposits as of June 30, 2022 and 2021 were $1,086 thousand and |
| Fair Value Measurements | Fair Value Measurements — of non-performance risk, Fair value measurements do not include transaction costs. A fair value hierarchy is used to prioritize the quality and reliability of the information used to determine fair values. Categorization within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The fair value hierarchy is defined into the following three categories: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. We use a Black-Scholes option valuation model to determine the grant date fair value our employee stock options and a Monte Carlo Simulation model to determine the grant date fair value of market-based stock grants. Both models use Level 2 inputs. See note 11—Share Based Compensation for a description of the inputs used. |
| Leases | Leases — Right-of-use Right-of-use (“ROU”) assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and lease liabilities are recognized at the lease commencement date based on the present value of the future lease payments over the lease term. When the rate implicit to the lease cannot be readily determined, we utilize our incremental borrowing rate in determining the present value of the future lease payments. The incremental borrowing rate is derived from information available at the lease commencement date and represents the rate of interest that we would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. The ROU asset includes any lease payments made and lease incentives received prior to the commencement date. Operating lease ROU assets could also include any cumulative prepaid or accrued rent when the lease payments are uneven throughout the lease term. The ROU assets and lease liabilities may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Lease liabilities rred . |
| Financial Instruments | Financial Instruments — d |
| Share Based Compensation | Share Based Compensation — additional paid-in capital. e |
| Loss per Common Share | Loss per Common Share — |
| Income Taxes | Income Taxes — each year-end. In evaluating our ability to recover our deferred tax assets, management considers all available positive and negative evidence, including scheduled reversals of deferred tax liabilities, projected future taxable income, tax planning strategies and recent financial operations. In projecting future taxable income, we develop assumptions including the amount of future state and federal pretax operating income, the reversal of temporary differences, and the implementation of feasible and prudent tax planning strategies. These assumptions require significant judgment about the forecasts of future taxable income and the assumptions are consistent with the plans and estimates that we use to manage the underlying businesses. A valuation allowance is recorded against deferred tax assets if we believe it is more likely than not the related tax benefits will not be realized. We evaluate uncertain tax positions in a two-step process, the more-likely-than-not recognition |
| Reclassifications | Reclassifications Certain reclassifications have been made to prior years’ reported amounts in order to conform to the current year presentation. These reclassifications did not impact our previously reported net income (loss), stockholders’ equity or cash flows. |
| Recently Issued Accounting Pronouncements | Recently Issued Accounting Pronouncements In August 2020, FASB issued ASU No. 2020-06–Debt–Debt with 470-20) (Subtopic 815-40): Convertible Instruments and Contracts in an Entity’s Own Equity. The update addresses issues identified as a result of the complexity associated with applying GAAP for certain financial instruments with characteristics of liabilities and equity. The update is effective for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years and with early adoption permitted. We do not expect ASU 2020-06 In May 2021, FASB issued ASU No. 2021-04—Earnings Per 470-50), (Subtopic 815-40) |
