Subsequent Event - Summary of Fair Value of Net Assets Acquired (Detail) (Talon Therapeutics, Inc. [Member], Subsequent Event [Member], USD $) In Thousands, unless otherwise specified	Jul. 17, 2013
Talon Therapeutics, Inc. [Member] | Subsequent Event [Member]
Business Acquisition [Line Items]
Cash and equivalents	$ 131
Inventory	611
Prepaid expenses and other current assets	602
Property and equipment	30
Identifiable intangible assets	46,300
Goodwill	20,606
Total assets acquired	68,280
Accounts payable & accrued liabilities	6,870
Contingent value rights	6,500
Deferred tax liability	17,300
Total liabilities assumed	30,670
Net assets acquired	$ 37,610