Related Party - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended
	Dec. 30, 2009	Dec. 31, 2012	Dec. 31, 2011
Related Party Transaction [Line Items]
Square footage of leased space	26,000
Net payable to Fidia		0.7	0.8
Fidia Farmaceutici Spa
Related Party Transaction [Line Items]
Issuance of common stock in connection with acquisition	1,981,192
Percentage of ownership interests		14.30%	14.50%