General	3 Months Ended
Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	GENERAL In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments (consisting only of normal recurring adjustments) necessary to present fairly the financial position of Stillwater Mining Company (the “Company”) at March 31, 2016, and the results of its operations and cash flows for the three months ended March 31, 2016 and 2015, respectively. The results of operations for the first three months of 2016 are not necessarily indicative of the results to be expected for the 2016 year. The accompanying consolidated financial statements in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's 2015 Annual Report on Form 10-K. All intercompany transactions and balances have been eliminated in consolidation. The preparation of the Company’s consolidated financial statements in conformity with United States generally accepted accounting principles (U. S. GAAP) requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. The more significant areas requiring the use of management’s estimates relate to mineral reserves, reclamation and environmental obligations, valuation allowance for deferred tax assets, useful lives utilized for depreciation, amortization and accretion calculations, future cash flows from long-lived assets, and fair value of derivatives and other financial instruments. Actual results could differ from these estimates. On May 28, 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue it expects to be entitled to for the transfer of promised goods or services to customers. In August 2015, the FASB issued ASU 2015-14, Deferral of the Effective Date, which defers the effective date of ASU 2014-09 by one year to January 1, 2018. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP. The standard permits the use of either the retrospective or cumulative effect transition method. The Company continues to evaluate the effect that ASU 2014-09 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is not permitted. On April 7, 2015, as part of its initiative to simplify and reduce complexity in financial statements, the FASB issued ASU 2015-03, Interest - Imputation, (Subtopic 835-30): Simplifying the Presentation of Debt Issuance. This ASU requires the debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability. Also, it requires retrospective application for all prior periods presented in the financial statements and a disclosure of the nature of and reason for the change in accounting principle, the transition method, a description of the prior-period information that has been retrospectively adjusted and the effect of the change on the financial statement line items. ASU 2015-03 is effective for financial statements issued for fiscal years beginning after December 31, 2015, and interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been previously issued. The Company elected early adoption of ASU 2015-03 and has reclassified Deferred debt issue costs against the related liability for all periods presented. Prior to the adoption of ASU 2015-03, the balance reported at December 31, 2015 for total Long-term debt and capital lease obligations was $258.9 million, after adoption and reclassification of Deferred debt issue costs of $3.8 million, the total balance reported at December 31, 2015 is $255.1 million. On July 22, 2015, as part of its initiative to simplify and reduce complexity in financial statements, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. ASU 2015-11, which will change the measurement principle for inventory from the lower of cost or market to the lower of cost and net realizable value. ASU 2015-11 is effective for financial statements issued for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2015-11 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. The ASU requires prospective adoption and permits early application. On February 25, 2016, the FASB issued ASU 2016-02, Leases, (Topic 840), which requires an entity that leases assets, with terms of more than 12 months, to recognize on the balance sheet the assets and liabilities for the rights and obligations created by those leases. ASU 2016-02 is effective for financial statements issued for fiscal years beginning after December 31, 2018, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2016-02 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is permitted. On March 30, 2016, as part of its initiative to simplify and reduce complexity in the financial statements, the FASB issued ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employees Shared-Based Payment Accounting. The ASU will change several aspects within share based payments: (1) Accounting for Income Taxes, (2) Classification of Excess Tax Benefits on the Statement of Cash Flows, (3) Forfeitures, (4) Minimum Statutory Tax Withholding Requirements, (5) Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-Withholding Purposes, (6) Practical Expedient - Expected Term, (7) Intrinsic Value, and (8) Eliminating the Indefinite Deferral. ASU 2016-09 is effective for financial statements issued for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2016-09 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is permitted in any interim or annual period provided that the entire ASU is adopted.

GENERAL

In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments (consisting only of normal recurring adjustments) necessary to present fairly the financial position of Stillwater Mining Company (the “Company”) at March 31, 2016, and the results of its operations and cash flows for the three months ended March 31, 2016 and 2015, respectively. The results of operations for the first three months of 2016 are not necessarily indicative of the results to be expected for the 2016 year. The accompanying consolidated financial statements in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's 2015 Annual Report on Form 10-K. All intercompany transactions and balances have been eliminated in consolidation.

The preparation of the Company’s consolidated financial statements in conformity with United States generally accepted accounting principles (U. S. GAAP) requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. The more significant areas requiring the use of management’s estimates relate to mineral reserves, reclamation and environmental obligations, valuation allowance for deferred tax assets, useful lives utilized for depreciation, amortization and accretion calculations, future cash flows from long-lived assets, and fair value of derivatives and other financial instruments. Actual results could differ from these estimates.

On May 28, 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue it expects to be entitled to for the transfer of promised goods or services to customers. In August 2015, the FASB issued ASU 2015-14, Deferral of the Effective Date, which defers the effective date of ASU 2014-09 by one year to January 1, 2018. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP. The standard permits the use of either the retrospective or cumulative effect transition method. The Company continues to evaluate the effect that ASU 2014-09 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is not permitted.

On April 7, 2015, as part of its initiative to simplify and reduce complexity in financial statements, the FASB issued ASU 2015-03, Interest - Imputation, (Subtopic 835-30): Simplifying the Presentation of Debt Issuance. This ASU requires the debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability. Also, it requires retrospective application for all prior periods presented in the financial statements and a disclosure of the nature of and reason for the change in accounting principle, the transition method, a description of the prior-period information that has been retrospectively adjusted and the effect of the change on the financial statement line items. ASU 2015-03 is effective for financial statements issued for fiscal years beginning after December 31, 2015, and interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been previously issued. The Company elected early adoption of ASU 2015-03 and has reclassified Deferred debt issue costs against the related liability for all periods presented. Prior to the adoption of ASU 2015-03, the balance reported at December 31, 2015 for total Long-term debt and capital lease obligations was $258.9 million, after adoption and reclassification of Deferred debt issue costs of $3.8 million, the total balance reported at December 31, 2015 is $255.1 million.

On July 22, 2015, as part of its initiative to simplify and reduce complexity in financial statements, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. ASU 2015-11, which will change the measurement principle for inventory from the lower of cost or market to the lower of cost and net realizable value. ASU 2015-11 is effective for financial statements issued for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2015-11 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. The ASU requires prospective adoption and permits early application.

On February 25, 2016, the FASB issued ASU 2016-02, Leases, (Topic 840), which requires an entity that leases assets, with terms of more than 12 months, to recognize on the balance sheet the assets and liabilities for the rights and obligations created by those leases. ASU 2016-02 is effective for financial statements issued for fiscal years beginning after December 31, 2018, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2016-02 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is permitted.

On March 30, 2016, as part of its initiative to simplify and reduce complexity in the financial statements, the FASB issued ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employees Shared-Based Payment Accounting. The ASU will change several aspects within share based payments: (1) Accounting for Income Taxes, (2) Classification of Excess Tax Benefits on the Statement of Cash Flows, (3) Forfeitures, (4) Minimum Statutory Tax Withholding Requirements, (5) Classification of Employee Taxes Paid on the Statement of Cash Flows When an Employer Withholds Shares for Tax-Withholding Purposes, (6) Practical Expedient - Expected Term, (7) Intrinsic Value, and (8) Eliminating the Indefinite Deferral. ASU 2016-09 is effective for financial statements issued for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The Company is evaluating the effect that ASU 2016-09 will have on its consolidated financial statements and disclosures and has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting. Early application is permitted in any interim or annual period provided that the entire ASU is adopted.