Organization, Business and Summary of Significant Accounting Policies - Summary of Revenue from Contracts with Customers (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Revenues	$ 81,650	$ 64,381	$ 157,100	$ 142,652
eDiscovery Services [Member]
Disaggregation Of Revenue [Line Items]
Revenues	50,800	45,402	98,954	99,035
Managed Review [Member]
Disaggregation Of Revenue [Line Items]
Revenues	19,904	9,706	35,484	22,832
Legal Technology Services [Member]
Disaggregation Of Revenue [Line Items]
Revenues	70,704	55,108	134,438	121,867
Data Recovery [Member]
Disaggregation Of Revenue [Line Items]
Revenues	$ 10,946	$ 9,273	$ 22,662	$ 20,785