Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

Name:	us-gaap_BusinessCombinationContingentConsiderationLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Business Combinations and Contingent Consideration - Acquisition-Date Fair Value of Consideration Transferred (Detail) - USD ($) $ in Thousands	1 Months Ended
	Mar. 31, 2013	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Ligand Contingent Consideration (Note 10 (b))		$ 0	$ 5,227
Captisol-enabled, propylene glycol-free melphalan rights [Member]
Business Acquisition [Line Items]
Cash consideration	$ 3,000
Ligand Contingent Consideration (Note 10 (b))	4,700
Total purchase consideration	$ 7,700