Nature of Business	6 Months Ended
Jun. 30, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business The Medicines Company (the Company) is a global biopharmaceutical company focused on saving lives, alleviating suffering and improving the economic efficiency of the world's leading hospitals. The Company markets Angiomax^®(bivalirudin), Recothrom^®Thrombin, topical (Recombinant) andCleviprex^® (clevidipine) injectable emulsion. The Company also has a pipeline of acute and intensive care hospital products in development, including three late-stage development product candidates, cangrelor, oritavancin and IONSYS^TM (fentanyl iontophoretic transdermal system) and early stage development product candidates MDCO-216 and ALN-PCS02 and ALN-PCSsc of its ALN-PCS program. The Company believes that these marketed products and products in development possess favorable attributes that competitive products do not provide, can satisfy unmet medical needs in the acute and intensive care hospital product market and offer, or, in the case of its products in development, have the potential to offer, improved performance to hospital businesses. In addition to these products and product candidates, the Company sells a ready-to-use formulation of Argatroban and has a portfolio of ten generic drugs, which the Company refers to as its acute care generic products, that the Company has the non-exclusive right to market in the United States. The Company began selling three of its acute care generic products, midazolam, ondansetron and rocuronium, in the first quarter of 2013. The Company also co-promotes the oral tablet antiplatelet medicine BRILINTA^® (ticagrelor) in the United States, as part of its global collaboration agreement with AstraZeneca LP (AstraZeneca). On August 5, 2013, the Company completed its acquisition of all of the outstanding equity of ProFibrix B.V. (ProFibrix) pursuant to a share purchase agreement entered into with ProFibrix and its equityholders on June 4, 2013. Upon the completion of the acquisition, ProFibrix became a wholly owned subsidiary of the Company. Under the share purchase agreement, the closing of the transaction was subject to the Company's satisfactory review of the then pending Phase 3 clinical trial results of ProFibrix's lead biologic, Fibrocaps™. Fibrocaps is a dry powder topical formulation of fibrinogen and thrombin being developed to help stop bleeding during surgery. Following the Company's review of the Phase 3 trial results, on August 2, 2013, the Company notified ProFibrix that it wished to proceed with the consummation of the transaction.

Nature of Business

The Medicines Company (the Company) is a global biopharmaceutical company focused on saving lives, alleviating suffering and improving the economic efficiency of the world's leading hospitals. The Company markets Angiomax^®(bivalirudin), Recothrom^®Thrombin, topical (Recombinant) andCleviprex^® (clevidipine) injectable emulsion. The Company also has a pipeline of acute and intensive care hospital products in development, including three late-stage development product candidates, cangrelor, oritavancin and IONSYS^TM (fentanyl iontophoretic transdermal system) and early stage development product candidates MDCO-216 and ALN-PCS02 and ALN-PCSsc of its ALN-PCS program. The Company believes that these marketed products and products in development possess favorable attributes that competitive products do not provide, can satisfy unmet medical needs in the acute and intensive care hospital product market and offer, or, in the case of its products in development, have the potential to offer, improved performance to hospital businesses.

In addition to these products and product candidates, the Company sells a ready-to-use formulation of Argatroban and has a portfolio of ten generic drugs, which the Company refers to as its acute care generic products, that the Company has the non-exclusive right to market in the United States. The Company began selling three of its acute care generic products, midazolam, ondansetron and rocuronium, in the first quarter of 2013. The Company also co-promotes the oral tablet antiplatelet medicine BRILINTA^® (ticagrelor) in the United States, as part of its global collaboration agreement with AstraZeneca LP (AstraZeneca).

On August 5, 2013, the Company completed its acquisition of all of the outstanding equity of ProFibrix B.V. (ProFibrix) pursuant to a share purchase agreement entered into with ProFibrix and its equityholders on June 4, 2013. Upon the completion of the acquisition, ProFibrix became a wholly owned subsidiary of the Company. Under the share purchase agreement, the closing of the transaction was subject to the Company's satisfactory review of the then pending Phase 3 clinical trial results of ProFibrix's lead biologic, Fibrocaps™. Fibrocaps is a dry powder topical formulation of fibrinogen and thrombin being developed to help stop bleeding during surgery. Following the Company's review of the Phase 3 trial results, on August 2, 2013, the Company notified ProFibrix that it wished to proceed with the consummation of the transaction.