Subsequent Events - Summary of Elements of Purchase Price of Acquisitions (Detail) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
		Jan. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Cash			$ 175,450	$ 87,285	$ 48,961
Common Stock			25,000	4,047	5,634
Total Purchase Price			$ 243,865	$ 98,183	$ 58,394
MSE Group | Subsequent Event
Subsequent Event [Line Items]
Cash	[1]	$ 6,272
Common Stock	[2]	2,271
Other Purchase Price Component	[3]	12,014
Total Purchase Price		$ 20,557

[1] The cash portion of the MSE purchase price was funded through cash on hand.

[2] The common stock component was paid through the issuance of 71,740 shares of common stock.  

[3] The other purchase price components consist of a target working capital amount, purchase price true ups and contingent consideration. The contingent consideration element of the purchase price is related to earn-outs which are based on the expected achievement of revenue or earnings thresholds as of the date of the acquisition and for which the maximum potential amount is limited.