Milestone Payments

No definition available.

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- Definition

Product Rights [Line Items]

+ References

No definition available.

+ Details

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- 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

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Balance Type:	na
Period Type:	duration

- 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=66006027&loc=d3e16323-109275

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Remaining amortization period 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

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- Definition

Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for foreign currency translation adjustments and purchase accounting adjustments.

+ References

No definition available.

+ Details

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph ((a)(1),(b))
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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Period Type:	instant

- Details

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Balance Sheet Account Detail - Components of Intangible Assets Net of Accumulated Amortization (Detail) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended	12 Months Ended
	May 29, 2013	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Product Rights [Line Items]
Historical Cost				$ 305,668	$ 305,668
Accumulated Amortization				(128,213)	(102,797)
Foreign Currency Translation				(5,038)	(4,353)
Impairment				(8,183)	(8,183)
Net Amount				164,234	190,335
Ligand Pharmaceuticals Inc [Member]
Product Rights [Line Items]
Milestone payments		$ 6,000
MARQIBO IPR&D (NHL and further ALL indications) [Member]
Product Rights [Line Items]
Historical Cost				17,600	17,600
Net Amount				17,600	17,600
EVOMELA IPR&D [Member]
Product Rights [Line Items]
Historical Cost				7,700	7,700
Net Amount				$ 7,256	7,700
Full Amortization Period (months)				156 months
Remaining Amortization Period (months)				147 months
BELEODAQ distribution rights [Member]
Product Rights [Line Items]
Historical Cost				$ 25,000	25,000
Accumulated Amortization				(4,688)	(2,812)
Net Amount				$ 20,312	22,188
Full Amortization Period (months)				160 months
Remaining Amortization Period (months)				130 months
MARQIBO distribution rights [Member]
Product Rights [Line Items]
Historical Cost				$ 26,900	26,900
Accumulated Amortization				(12,863)	(8,544)
Net Amount				$ 14,037	18,356
Full Amortization Period (months)				81 months
Remaining Amortization Period (months)				39 months
FOLOTYN distribution rights [Member]
Product Rights [Line Items]
Historical Cost				$ 118,400	118,400
Accumulated Amortization				(41,036)	(29,474)
Impairment	$ (1,000)
Net Amount				$ 77,364	88,926
Full Amortization Period (months)				152 months
Remaining Amortization Period (months)				71 months
ZEVALIN distribution rights [Member] \| United States [Member]
Product Rights [Line Items]
Historical Cost				$ 41,900	41,900
Accumulated Amortization				(34,083)	(30,608)
Net Amount				$ 7,817	11,292
Full Amortization Period (months)				123 months
Remaining Amortization Period (months)				27 months
ZEVALIN distribution rights [Member] \| Ex-U.S. [Member]
Product Rights [Line Items]
Historical Cost				$ 23,490	23,490
Accumulated Amortization				(13,649)	(12,632)
Foreign Currency Translation				(5,038)	(4,353)
Impairment				0
Net Amount				$ 4,803	6,505
Full Amortization Period (months)				96 months
Remaining Amortization Period (months)				39 months
FUSILEV distribution rights [Member]
Product Rights [Line Items]
Historical Cost				$ 16,778	16,778
Accumulated Amortization				(9,618)	(9,618)
Impairment				(7,160)	(7,160)
Net Amount				$ 0	0
Full Amortization Period (months)				56 months
Remaining Amortization Period (months)				0 months
FOLOTYN out-License [Member]
Product Rights [Line Items]
Historical Cost				$ 27,900	27,900
Accumulated Amortization				(11,832)	(9,109)
Impairment				(1,023)	(1,023)
Net Amount				$ 15,045	$ 17,768
Full Amortization Period (months)				110 months
Remaining Amortization Period (months)				67 months
EVOMELA [Member]
Product Rights [Line Items]
Historical Cost		$ 7,700
Fusilev [Member]
Product Rights [Line Items]
Impairment			$ (7,200)