Summary of Disaggregation of Product Revenues from Contracts with Customers by Major Product Line (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 108,648	$ 94,060	$ 87,462	$ 76,090	$ 69,474	$ 69,445	$ 70,692	$ 60,634	$ 366,260		$ 270,245		$ 194,032
Product
Disaggregation of Revenue [Line Items]
Revenue									366,136	[1]	270,097	[2]	193,891
Royalty and Other Revenue
Disaggregation of Revenue [Line Items]
Revenue									$ 124		$ 148		$ 141

[1] 2020 revenue for filtration products includes revenue related to EMT from July 13, 2020, NMS from October 20, 2020 and ARTeSYN from December 3, 2020.

[2] 2019 revenue includes process analytics revenue related to C Technologies from June 1, 2019 through December 31, 2019.