Description of Business	12 Months Ended
Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	DESCRIPTION OF BUSINESS AMAG Pharmaceuticals, Inc., a Delaware corporation, was founded in 1981. We are a biopharmaceutical company focused on developing and delivering important therapeutics, conducting clinical research in areas of unmet need and creating education and support programs for the patients and families we serve. Our currently marketed products support the health of patients in the areas of maternal and women’s health, anemia management and cancer supportive care, including Makena^® (hydroxyprogesterone caproate injection), Intrarosa^®(prasterone) vaginal inserts, Feraheme^® (ferumoxytol injection) for intravenous (“IV”) use, and MuGard^® Mucoadhesive Oral Wound Rinse. In addition, in February 2017, we acquired the rights to research, develop and commercialize bremelanotide in North America. Through services related to the preservation of umbilical cord blood stem cell and cord tissue units operated through Cord Blood Registry^®(“CBR”), we also help families to preserve newborn stem cells, which are used today in transplant medicine for certain cancers and blood, immune and metabolic disorders, and which we believe have the potential to play a valuable role in the ongoing development of regenerative medicine. We are subject to risks common to companies in the pharmaceutical industry including, but not limited to (as such risks pertain to our business) our ability to successfully commercialize our products and services, intense competition, including from generic products; maintaining and defending the proprietary nature of our technology; our dependence upon third-party manufacturers and our potential inability to obtain raw or other materials; our reliance on and the extent of reimbursement from third parties for the use of our products, including the impact of generic competitors, Makena’s high Medicaid reimbursement concentration and the limited level of reimbursement for Intrarosa; our ability to expand our product portfolio through business development transactions; the approval of bremelanotide and our ability to commercialize bremelanotide, if approved; employee retention and our ability to manage our expanded product portfolio and operations; potential litigation, including securities and product liability suits; our ability to work effectively and collaboratively with our licensors; our reliance on other third parties in our business, including to conduct our clinical trials and undertake our product and distribution; our ability to attract and retain key employees; if our storage facility in Tucson, Arizona is damaged or destroyed; our potential failure to comply with federal and state healthcare fraud and abuse laws, marketing disclosure laws, cord blood and tissue regulations and laws or other federal and state laws and regulations and potential civil or criminal penalties as a result thereof; uncertainties regarding reporting and payment obligations under government pricing programs; post-approval commitments for Makena; our ability to comply with data protection laws and regulations; the impact of disruptions to our information technology systems; our level of and ability to repay our indebtedness; our access to sufficient capital; the availability of net operating loss carryforwards and other tax assets; potential differences between actual future results and the estimates or assumptions used by us in preparation of our consolidated financial statements, including goodwill and intangible assets; the volatility of our stock price; the potential fluctuation of our operating results; and provisions in our charter, by-laws and certain contracts that discourage an acquisition of our company. Throughout this Annual Report on Form 10-K, AMAG Pharmaceuticals, Inc. and our consolidated subsidiaries are collectively referred to as “the Company,” “AMAG,” “we,” “us,” or “our.”

DESCRIPTION OF BUSINESS

AMAG Pharmaceuticals, Inc., a Delaware corporation, was founded in 1981. We are a biopharmaceutical company focused on developing and delivering important therapeutics, conducting clinical research in areas of unmet need and creating education and support programs for the patients and families we serve. Our currently marketed products support the health of patients in the areas of maternal and women’s health, anemia management and cancer supportive care, including Makena^® (hydroxyprogesterone caproate injection), Intrarosa^®(prasterone) vaginal inserts, Feraheme^® (ferumoxytol injection) for intravenous (“IV”) use, and MuGard^® Mucoadhesive Oral Wound Rinse. In addition, in February 2017, we acquired the rights to research, develop and commercialize bremelanotide in North America. Through services related to the preservation of umbilical cord blood stem cell and cord tissue units operated through Cord Blood Registry^®(“CBR”), we also help families to preserve newborn stem cells, which are used today in transplant medicine for certain cancers and blood, immune and metabolic disorders, and which we believe have the potential to play a valuable role in the ongoing development of regenerative medicine.

We are subject to risks common to companies in the pharmaceutical industry including, but not limited to (as such risks pertain to our business) our ability to successfully commercialize our products and services, intense competition, including from generic products; maintaining and defending the proprietary nature of our technology; our dependence upon third-party manufacturers and our potential inability to obtain raw or other materials; our reliance on and the extent of reimbursement from third parties for the use of our products, including the impact of generic competitors, Makena’s high Medicaid reimbursement concentration and the limited level of reimbursement for Intrarosa; our ability to expand our product portfolio through business development transactions; the approval of bremelanotide and our ability to commercialize bremelanotide, if approved; employee retention and our ability to manage our expanded product portfolio and operations; potential litigation, including securities and product liability suits; our ability to work effectively and collaboratively with our licensors; our reliance on other third parties in our business, including to conduct our clinical trials and undertake our product and distribution; our ability to attract and retain key employees; if our storage facility in Tucson, Arizona is damaged or destroyed; our potential failure to comply with federal and state healthcare fraud and abuse laws, marketing disclosure laws, cord blood and tissue regulations and laws or other federal and state laws and regulations and potential civil or criminal penalties as a result thereof; uncertainties regarding reporting and payment obligations under government pricing programs; post-approval commitments for Makena; our ability to comply with data protection laws and regulations; the impact of disruptions to our information technology systems; our level of and ability to repay our indebtedness; our access to sufficient capital; the availability of net operating loss carryforwards and other tax assets; potential differences between actual future results and the estimates or assumptions used by us in preparation of our consolidated financial statements, including goodwill and intangible assets; the volatility of our stock price; the potential fluctuation of our operating results; and provisions in our charter, by-laws and certain contracts that discourage an acquisition of our company.

Throughout this Annual Report on Form 10-K, AMAG Pharmaceuticals, Inc. and our consolidated subsidiaries are collectively referred to as “the Company,” “AMAG,” “we,” “us,” or “our.”