Business Combination, Collaboration Term

No definition available.

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Option

+ References

No definition available.

+ Details

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Namespace Prefix:	mdco_
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Period Type:	instant

- Details

Name:	mdco_IntangibleAssetsAndGoodwillLineItems
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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=25498275&loc=d3e2207-128464

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsNet
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Period Type:	instant

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Intangible Assets and Goodwill (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended		1 Months Ended	3 Months Ended							9 Months Ended		9 Months Ended		9 Months Ended		9 Months Ended			9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Feb. 28, 2013 Bristol-Myers Squibb [Member]	Sep. 30, 2013 Bristol-Myers Squibb [Member]	Sep. 30, 2013 Incline Therapeutics, Inc. [Member]	Aug. 05, 2013 ProFibrix [Member]	Sep. 30, 2013 In Process Research and Development [Member]	Dec. 31, 2012 In Process Research and Development [Member]	Sep. 30, 2013 Recothrom Option [Member]	Dec. 31, 2012 Recothrom Option [Member]	Sep. 30, 2013 Customer relationships [Member]	Dec. 31, 2012 Customer relationships [Member]	Sep. 30, 2013 Selling rights agreement [Member]	Dec. 31, 2012 Selling rights agreement [Member]	Sep. 30, 2013 Trademarks [Member]	Dec. 31, 2012 Trademarks [Member]	Sep. 30, 2013 Product licenses [Member]	Dec. 31, 2012 Product licenses [Member]	Feb. 28, 2013 Product licenses [Member] Bristol-Myers Squibb [Member]	Sep. 30, 2013 Cleviprex milstones [Member]	Dec. 31, 2012 Cleviprex milstones [Member]	Sep. 30, 2013 In Process Research and Development [Member] Incline Therapeutics, Inc. [Member]	Jan. 31, 2013 In Process Research and Development [Member] Incline Therapeutics, Inc. [Member]	Sep. 30, 2013 In Process Research and Development [Member] ProFibrix [Member]
Intangible Assets and Goodwill [Line Items]
Weighted Average Useful Life	6 years 1 month 6 days			2 years							8 years		5 years 8 months 12 days		8 years		5 years 8 months 12 days			13 years
Gross Carrying Amount	$ 92,606	$ 60,606									$ 7,457	$ 7,457	$ 9,125	$ 9,125	$ 3,024	$ 3,024	$ 71,000	$ 39,000		$ 2,000	$ 2,000
Accumulated Amortization	(27,832)	(10,530)									(5,250)	(4,106)	(5,270)	(3,469)	(2,129)	(1,665)	(14,999)	(1,129)		(184)	(161)
Net Carrying Amount	64,774	50,076									2,207	3,351	3,855	5,656	895	1,359	56,001	37,871		1,816	1,839
Collaboration term			2 years
Intangible asset						176,000													32,000			250,000	250,000	176,000
Option			62,000		62,000
Indefinite-lived Intangible Assets	$ 557,500	$ 69,500					$ 495,500	$ 69,500	$ 62,000	$ 0