Fair Value Disclosures - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in fair value of contingent consideration liability	$ (10,674,000)
Fair value of liabilities transferred from Level 1 to Level 2	0
Fair value of liabilities transferred from Level 2 to Level 1	0
Fair value of assets transferred from Level 1 to Level 2	0
Fair value of assets transferred from Level 2 to Level 1	0
Fair value, measurements, nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Estimated fair value of the debt		$ 496,800,000
R&D expense [Member] \| MDV9300 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in fair value of contingent consideration liability	2,600,000
SG&A expense [Member] \| MDV9300 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Change in fair value of contingent consideration liability	$ 7,700,000

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Convertible Security
-URI http://asc.fasb.org/extlink&oid=6509036

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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