Net Product Sales by Geographic Region and Product Line - Schedule of Product Sales, Net by Product Line (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Sales Information [Line Items]
Product sales, net	$ 35,241	$ 38,413
Percentage of product sales, net	100.00%	100.00%
FUSILEV [Member]
Sales Information [Line Items]
Product sales, net	$ 15,209	$ 20,167
FOLOTYN [Member]
Sales Information [Line Items]
Product sales, net	13,292	9,316
ZEVALIN [Member]
Sales Information [Line Items]
Product sales, net	2,783	4,223
MARQIBO [Member]
Sales Information [Line Items]
Product sales, net	929	1,893
BELEODAQ [Member]
Sales Information [Line Items]
Product sales, net	$ 3,028	$ 2,814
Sales [Member]
Sales Information [Line Items]
Percentage of product sales, net	100.00%	100.00%
Sales [Member] | FUSILEV [Member]
Sales Information [Line Items]
Percentage of product sales, net	43.20%	52.50%
Sales [Member] | FOLOTYN [Member]
Sales Information [Line Items]
Percentage of product sales, net	37.70%	24.30%
Sales [Member] | ZEVALIN [Member]
Sales Information [Line Items]
Percentage of product sales, net	7.90%	11.00%
Sales [Member] | MARQIBO [Member]
Sales Information [Line Items]
Percentage of product sales, net	2.60%	4.90%
Sales [Member] | BELEODAQ [Member]
Sales Information [Line Items]
Percentage of product sales, net	8.60%	7.30%