Organization, Business and Summary of Significant Accounting Policies - Summary of Revenue from Contracts with Customers (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Revenues	$ 75,450	$ 78,271
eDiscovery Services [Member]
Disaggregation Of Revenue [Line Items]
Revenues	48,154	53,633
Managed Review [Member]
Disaggregation Of Revenue [Line Items]
Revenues	15,580	13,126
Legal Technology Services [Member]
Disaggregation Of Revenue [Line Items]
Revenues	63,734	66,759
Data Recovery [Member]
Disaggregation Of Revenue [Line Items]
Revenues	$ 11,716	$ 11,512