Description of Business	12 Months Ended
Dec. 31, 2016
Description of Business
Description of Business	1. Description of Business Corporate Information, Status of Operations, and Management Plans Amicus Therapeutics, Inc. (the "Company") is a global patient-focused biotechnology company engaged in the discovery, development, and commercialization of a diverse set of novel treatments for patients living with devastating rare and orphan diseases. The lead product, migalastat HCl is a small molecule that can be used as a monotherapy and in combination with enzyme replacement of therapy ("ERT") for Fabry disease. The Company's Fabry franchise strategy is to develop migalastat HCl (which the Company may refer to as "migalastat") for all patients with Fabry disease as a monotherapy for patients with amenable mutations and in combination with ERT for all other patients. In May 2016, the Company announced that the European Commission ("EC") had granted full approval for the oral small molecule pharmacological chaperone Galafold™ (migalastat) as a first-line therapy for long-term treatment of adults and adolescents aged 16 years and older with a confirmed diagnosis of Fabry disease (alpha-galactosidase A deficiency) and who have an amenable mutation. The approved label includes 313 Fabry-causing mutations, which represent up to half of all patients with Fabry disease. The Company commenced commercial shipments of Galafold in the EU in the second quarter of 2016 and recognized net product sales of $5.0 million in 2016. Also in the pipeline, SD-101 is a product candidate in late-stage development, as a potential first-to-market therapy for the chronic, rare connective tissue disorder Epidermolysis Bullosa ("EB"). The Company is also leveraging its biologics and Chaperone-Advanced Replacement Therapy ("CHART™") platform technologies to develop novel ERT products for Pompe disease, Fabry disease, and potentially other lysosomal storage disorders ("LSDs"). The Company is also investigating preclinical and discovery programs in other rare and devastating diseases including cyclin-dependent kinase-like 5 ("CDKL5") deficiency. The Company believes that the platform technologies and advanced product pipeline uniquely position the Company at the forefront of advanced therapies to treat a range of devastating rare and orphan diseases. On December 21, 2016, the Company issued $250 million aggregate principal amount of 3.00% unsecured Convertible Senior Notes due 2023 (the "Convertible Notes"), in a private offering to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"). Interest is payable semiannually on June 15 and December 15 of each year, beginning on June 15, 2017. The Notes will mature on December 15, 2023, unless earlier repurchased, redeemed, or converted in accordance with their terms. The Notes are convertible at the option of the holders, under certain circumstances and during certain periods, into cash, shares of the Company's common stock, par value $0.01 per share ("Common Stock"), or a combination thereof. The net proceeds from the issuance of the Convertible Note offering were $243.1 million, after deducting fees and estimated expenses payable by the Company. In addition, the Company used approximately $13.5 million of the net proceeds from the issuance of the Convertible Notes to pay the cost of the capped call transactions ("Capped Call Confirmations") that the Company entered into in connection with the issuance of the Convertible Notes. For additional information, see "— Note 16. Debt Instruments and Related Party Transactions." In July 2016, the Company expanded its biologics pipeline with a new preclinical program for CDKL5 deficiency, a rare and devastating genetic neurological disease for which there is no currently approved treatment. The Company has obtained the rights and related intellectual property to a preclinical CDKL5 program through its acquisition of MiaMed, Inc ("MiaMed"). The aggregate value of the deal was approximately $89.5 million, which included an upfront payment of $6.5 million and Company stock, cash and potential milestones of up to $83.0 million. For additional information, see "— Note 3. Acquisitions". Beginning in April 2016 and through July 2016, the Company sold 15.0 million shares of Common Stock under an at-the-market ("ATM") equity program with Cowen and Company, LLC ("Cowen") acting as sales agent. Cowen was compensated at a fixed commission rate up to 3.0%. The ATM sales agreement resulted in net proceeds of $97.1 million, after Cowen's commission of $2.7 million and other expenses of $0.2 million. The Company has completed all sales under the ATM equity program. The Company had an accumulated deficit of approximately $779.6 million at December 31, 2016 and anticipates incurring losses through the fiscal year ending December 31, 2017 and beyond. The Company has been able to fund its operating losses to date through stock offering, debt issuances, and payments from partners during the terms of the collaboration agreements and other financing arrangements. The Company believes that its existing cash and cash equivalents and short-term investments will be sufficient to fund the current operating plan into the second half of 2018.

1. Description of Business

Corporate Information, Status of Operations, and Management Plans

Amicus Therapeutics, Inc. (the "Company") is a global patient-focused biotechnology company engaged in the discovery, development, and commercialization of a diverse set of novel treatments for patients living with devastating rare and orphan diseases. The lead product, migalastat HCl is a small molecule that can be used as a monotherapy and in combination with enzyme replacement of therapy ("ERT") for Fabry disease.

The Company's Fabry franchise strategy is to develop migalastat HCl (which the Company may refer to as "migalastat") for all patients with Fabry disease as a monotherapy for patients with amenable mutations and in combination with ERT for all other patients. In May 2016, the Company announced that the European Commission ("EC") had granted full approval for the oral small molecule pharmacological chaperone Galafold™ (migalastat) as a first-line therapy for long-term treatment of adults and adolescents aged 16 years and older with a confirmed diagnosis of Fabry disease (alpha-galactosidase A deficiency) and who have an amenable mutation. The approved label includes 313 Fabry-causing mutations, which represent up to half of all patients with Fabry disease. The Company commenced commercial shipments of Galafold in the EU in the second quarter of 2016 and recognized net product sales of $5.0 million in 2016.

Also in the pipeline, SD-101 is a product candidate in late-stage development, as a potential first-to-market therapy for the chronic, rare connective tissue disorder Epidermolysis Bullosa ("EB"). The Company is also leveraging its biologics and Chaperone-Advanced Replacement Therapy ("CHART™") platform technologies to develop novel ERT products for Pompe disease, Fabry disease, and potentially other lysosomal storage disorders ("LSDs"). The Company is also investigating preclinical and discovery programs in other rare and devastating diseases including cyclin-dependent kinase-like 5 ("CDKL5") deficiency. The Company believes that the platform technologies and advanced product pipeline uniquely position the Company at the forefront of advanced therapies to treat a range of devastating rare and orphan diseases.

On December 21, 2016, the Company issued $250 million aggregate principal amount of 3.00% unsecured Convertible Senior Notes due 2023 (the "Convertible Notes"), in a private offering to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the "Securities Act"). Interest is payable semiannually on June 15 and December 15 of each year, beginning on June 15, 2017. The Notes will mature on December 15, 2023, unless earlier repurchased, redeemed, or converted in accordance with their terms. The Notes are convertible at the option of the holders, under certain circumstances and during certain periods, into cash, shares of the Company's common stock, par value $0.01 per share ("Common Stock"), or a combination thereof. The net proceeds from the issuance of the Convertible Note offering were $243.1 million, after deducting fees and estimated expenses payable by the Company. In addition, the Company used approximately $13.5 million of the net proceeds from the issuance of the Convertible Notes to pay the cost of the capped call transactions ("Capped Call Confirmations") that the Company entered into in connection with the issuance of the Convertible Notes. For additional information, see "— Note 16. Debt Instruments and Related Party Transactions."

In July 2016, the Company expanded its biologics pipeline with a new preclinical program for CDKL5 deficiency, a rare and devastating genetic neurological disease for which there is no currently approved treatment. The Company has obtained the rights and related intellectual property to a preclinical CDKL5 program through its acquisition of MiaMed, Inc ("MiaMed"). The aggregate value of the deal was approximately $89.5 million, which included an upfront payment of $6.5 million and Company stock, cash and potential milestones of up to $83.0 million. For additional information, see "— Note 3. Acquisitions".

Beginning in April 2016 and through July 2016, the Company sold 15.0 million shares of Common Stock under an at-the-market ("ATM") equity program with Cowen and Company, LLC ("Cowen") acting as sales agent. Cowen was compensated at a fixed commission rate up to 3.0%. The ATM sales agreement resulted in net proceeds of $97.1 million, after Cowen's commission of $2.7 million and other expenses of $0.2 million. The Company has completed all sales under the ATM equity program.

The Company had an accumulated deficit of approximately $779.6 million at December 31, 2016 and anticipates incurring losses through the fiscal year ending December 31, 2017 and beyond. The Company has been able to fund its operating losses to date through stock offering, debt issuances, and payments from partners during the terms of the collaboration agreements and other financing arrangements.

The Company believes that its existing cash and cash equivalents and short-term investments will be sufficient to fund the current operating plan into the second half of 2018.