BUSINESS AND BASIS OF PRESENTATION (Policies)	6 Months Ended
BUSINESS AND BASIS OF PRESENTATION (Policies)	Jun. 30, 2015
Accounting Policies [Abstract]
Business	*Business* Sarepta Therapeutics, Inc. (together with its wholly-owned subsidiaries “Sarepta” or the “Company”) is a biopharmaceutical company focused on the discovery and development of unique RNA-targeted therapeutics for the treatment of rare, infectious and other diseases. Applying its proprietary, highly-differentiated and innovative platform technologies, the Company is able to target a broad range of diseases and disorders through distinct RNA-targeted mechanisms of action. The Company is primarily focused on rapidly advancing the development of its potentially disease-modifying Duchenne muscular dystrophy (“DMD”) drug candidates, including its lead DMD product candidate, eteplirsen, designed to skip exon 51. The Company is also developing therapeutics using its technology for the treatment of infectious diseases, such as drug resistant bacteria, rare and other human diseases. The Company has not generated any revenue from product sales to date and there can be no assurance that revenue from product sales will be achieved. Even if it does achieve revenue from product sales, the Company is likely to continue to incur operating losses in the near term. As of June 30, 2015, the Company had approximately $157.7 million of cash, cash equivalents and investments, consisting of $69.5 million of cash and cash equivalents, $87.3 million of short-term investments and $0.8 million of restricted cash and investments. The Company believes that its balance of cash, cash equivalents and investments is sufficient to fund its current operational plan for the next twelve months, though it may pursue additional cash resources through public or private financings, seek additional government contracts and establish collaborations with or license its technology to other companies.
Basis of Presentation	*Basis of Presentation* The accompanying unaudited condensed consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), reflect the accounts of Sarepta Therapeutics, Inc. and its wholly-owned subsidiaries. All inter-company transactions between and among its consolidated subsidiaries have been eliminated. Management has determined that the Company operates in one segment: the development of pharmaceutical products on its own behalf or in collaboration with others. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.
Estimates and Uncertainties	*Estimates and Uncertainties* The preparation of the unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, equity, revenue, expenses and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include the valuation of stock-based awards, research and development expenses, revenue recognition and income tax.
Recent Accounting Pronouncements	In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2015-03, which simplifies presentation of debt issuance costs. The amendments in this update require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU No. 2015-03 will be effective for fiscal years beginning after December 15, 2015, with early adoption permitted. The Company has elected to adopt this ASU early and the adoption of this guidance did not have a material effect on its consolidated financial statements. For additional information, please read Note 7, Long-term Debt of the unaudited condensed consolidated financial statements. In August 2014, the FASB issued ASU No. 2014-15 which requires an entity’s management to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued or available to be issued. Substantial doubt about an entity’s ability to continue as a going concern exists when relevant conditions and events, considered in the aggregate, indicate that it is probable that the entity will not be able to meet its obligations as they become due within one year after the date that the financial statements are issued or available to be issued. If conditions or events raise substantial doubt about an entity’s ability to continue as a going concern, but the substantial doubt is alleviated as a result of consideration of management’s plans to mitigate those relevant conditions or events, the entity is required to disclose (1) principal conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern, (2) management’s evaluation of the significance of those conditions or events in relation to the entity’s ability to meet its obligations, and (3) management’s plans that alleviate substantial doubt about the entity’s ability to continue as a going concern. However, if conditions or events raise substantial doubt about an entity’s ability to continue as a going concern, and substantial doubt is not alleviated after consideration of management’s plans, an entity should include a statement in a footnote indicating that there is substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued or available to be issued. ASU No. 2014-15 is effective for the annual period ending after December 15, 2016, with early adoption permitted. The Company has not adopted this guidance as of June 30, 2015, and based on the Company’s financial condition as of June 30, 2015, the Company does not expect the adoption of this guidance to have any impact on the current period financial statements. In May 2014, the FASB issued ASU No. 2014-09, which amends the guidance for accounting for revenue from contracts with customers. This ASU supersedes the revenue recognition requirements in Accounting Standards Codification Topic 605, Revenue Recognition, and creates a new Topic 606, Revenue from Contracts with Customers. Under the new guidance, a company is required to recognize revenue when it transfers goods or renders services to customers at an amount that it expects to be entitled to in exchange for these goods or services. This guidance is effective for the fiscal years beginning after December 15, 2016, with early adoption not permitted. In July 2015, the FASB decided to delay the effective date of this standard by one year, with early adoption only permitted in fiscal year 2017. Two adoption methods are permitted: retrospectively to all prior reporting periods presented, with certain practical expedients permitted; or retrospectively with the cumulative effect of initially adopting the ASU recognized at the date of initial application. The Company has not yet determined which adoption method it will utilize or the effect that the adoption of this guidance will have on its consolidated financial statements.