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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Namespace Prefix:	us-gaap_
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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
	Mar. 10, 2016	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2015	Jun. 30, 2013	Dec. 31, 2016	Apr. 30, 2016
Product Rights [Line Items]
Historical Cost			$ 305,668			$ 305,668
Accumulated Amortization			(135,319)			(128,213)
Foreign Currency Translation			(4,747)			(5,038)
Impairment			(8,183)			(8,183)
Net Amount			157,419			164,234
Ligand Pharmaceuticals Inc [Member]
Product Rights [Line Items]
Milestone payments	$ 6,000	$ 6,000
MARQIBO IPR&D (NHL indication) [Member]
Product Rights [Line Items]
Historical Cost			17,600			17,600
Accumulated Amortization			0			0
Foreign Currency Translation			0			0
Impairment			0			0
Net Amount			17,600			17,600
EVOMELA distribution rights [Member]
Product Rights [Line Items]
Historical Cost			7,700			7,700	$ 7,700
Accumulated Amortization			(592)			(444)
Foreign Currency Translation			0			0
Impairment			0			0
Net Amount			$ 7,108			7,256
Full Amortization Period (months)			156 months
Remaining Amortization Period (months)			144 months
BELEODAQ distribution rights [Member]
Product Rights [Line Items]
Historical Cost			$ 25,000			25,000
Accumulated Amortization			(5,156)			(4,688)
Foreign Currency Translation			0			0
Impairment			0			0
Net Amount			$ 19,844			20,312
Full Amortization Period (months)			160 months
Remaining Amortization Period (months)			127 months
MARQIBO distribution rights [Member]
Product Rights [Line Items]
Historical Cost			$ 26,900			26,900
Accumulated Amortization			(13,943)			(12,863)
Foreign Currency Translation			0			0
Impairment			0			0
Net Amount			$ 12,957			14,037
Full Amortization Period (months)			81 months
Remaining Amortization Period (months)			36 months
FOLOTYN distribution rights [Member]
Product Rights [Line Items]
Historical Cost			$ 118,400			118,400
Accumulated Amortization			(44,305)			(41,036)
Foreign Currency Translation			0			0
Impairment			0		$ (1,000)	0
Net Amount			$ 74,095			77,364
Full Amortization Period (months)			152 months
Remaining Amortization Period (months)			68 months
ZEVALIN distribution rights [Member] \| United States [Member]
Product Rights [Line Items]
Historical Cost			$ 41,900			41,900
Accumulated Amortization			(34,951)			(34,083)
Foreign Currency Translation			0			0
Impairment			0			0
Net Amount			$ 6,949			7,817
Full Amortization Period (months)			123 months
Remaining Amortization Period (months)			24 months
ZEVALIN distribution rights [Member] \| Ex-U.S. [Member]
Product Rights [Line Items]
Historical Cost			$ 23,490			23,490
Accumulated Amortization			(14,241)			(13,649)
Foreign Currency Translation			(4,747)			(5,038)
Impairment			0			0
Net Amount			$ 4,502			4,803
Full Amortization Period (months)			96 months
Remaining Amortization Period (months)			36 months
FUSILEV distribution rights [Member]
Product Rights [Line Items]
Historical Cost			$ 16,778			16,778
Accumulated Amortization			(9,618)			(9,618)
Foreign Currency Translation			0			0
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			(12,513)			(11,832)
Foreign Currency Translation			0			0
Impairment			(1,023)			(1,023)
Net Amount			$ 14,364			$ 15,045
Full Amortization Period (months)			110 months
Remaining Amortization Period (months)			64 months
FUSILEV [Member]
Product Rights [Line Items]
Impairment				$ (7,200)
EVOMELA [Member]
Product Rights [Line Items]
Historical Cost		$ 7,700