Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (102,670)	$ (92,464)
Other comprehensive (loss) income:
Foreign currency translation adjustment	(328)	315
Amounts reclassified from accumulated other comprehensive income	0	(9,665)
Other comprehensive income (loss)	(328)	(9,350)
Comprehensive loss	(102,998)	(101,814)
Less: comprehensive loss attributable to non-controlling interest	0	16
Comprehensive loss attributable to The Medicines Company	$ (102,998)	$ (101,798)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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