Disposal Group, Including Discontinued Operation, Assets, Contingent Asset, Noncurrent

No definition available.

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Namespace Prefix:	mdco_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Expenses on Disposition of Business

+ References

No definition available.

+ Details

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Namespace Prefix:	mdco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

+ Details

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- Details

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- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
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Period Type:

Dispositions (Narrative) (Details) - USD ($) $ in Thousands		3 Months Ended
Dispositions (Narrative) (Details) - USD ($) $ in Thousands	Jun. 21, 2016	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of businesses		$ 0	$ 174,068
Potential contingent proceeds from sale		143,700		$ 143,700
Non-Core ACC Products \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of businesses	$ 263,807
Potential contingent proceeds from sale	480,000	65,700
Gain on sale of assets	$ 288,301	288,300
Disposition related costs		$ 7,900