Acquisitions - Schedule of Unaudited Pro Forma Results of Operations (Detail) (Allos Therapeutics, Inc. [Member], As Restated [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012
Allos Therapeutics, Inc. [Member] | As Restated [Member]
Business Acquisition [Line Items]
Total revenues	$ 82,174	$ 153,367
Income from continuing operations	17,681	26,706
Net income	$ 11,182	$ 43,210
Basic net income per share	$ 0.19	$ 0.74
Diluted net income per share	$ 0.18	$ 0.68