Summary of Product Revenues by Product Line (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014
Revenue from External Customer [Line Items]
Product revenue	$ 25,500	$ 24,677	$ 29,170	$ 25,094	$ 21,449	$ 19,814	$ 21,457	$ 20,816	$ 104,441		$ 83,537	$ 60,431
Protein products
Revenue from External Customer [Line Items]
Product revenue									54,716		52,938	43,674
Filtration products
Revenue from External Customer [Line Items]
Product revenue									19,774	[1]	15,676	6,739	[2]
Chromatography products
Revenue from External Customer [Line Items]
Product revenue									29,520	[3]	14,613	9,811
Other
Revenue from External Customer [Line Items]
Product revenue									$ 431		$ 310	$ 207

[1] 2016 revenue for filtration products includes revenue related to the TangenX Acquisition from December 14, 2016 through December 31, 2016.

[2] 2014 revenue for filtration products includes revenue related to the Refine Acquisition from June 2, 2014 through December 31, 2014.

[3] 2016 revenue for chromatography products includes revenue related to the Atoll Acquisition from April 1, 2016 through December 31, 2016.