Summary of Significant Accounting Policies - Summary of Revenue and Adjusted EBITDA by Segment (Detail) - USD ($)
$ in Thousands
12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Mar. 31, 2019
Segment Revenue      
Total revenue $ 243,920 $ 305,463 $ 440,900
Segment Adjusted EBITDA      
Total Adjusted EBITDA (76,525) (147,188) (141,391)
Reconciliation of net loss to Adjusted EBITDA      
Net loss (183,619) (250,863) (183,533)
Interest (income), net (255) (6,244) (5,269)
Other (income) / expense, net (1,322) (1,340) 19
Depreciation and amortization 20,246 22,610 9,901
Stock-based compensation expense 88,425 44,838 37,491
Restructuring and other charges [1]   44,692  
Unallocated Corporate [Member]      
Segment Adjusted EBITDA      
Total Adjusted EBITDA (30,587) (28,460) (23,793)
Consumer & Research Services [Member]      
Segment Revenue      
Total revenue 243,866 299,907 437,919
Segment Adjusted EBITDA      
Total Adjusted EBITDA 12,796 (65,845) (85,822)
Therapeutics [Member]      
Segment Revenue      
Total revenue 54 5,556 2,981
Segment Adjusted EBITDA      
Total Adjusted EBITDA $ (58,734) $ (52,883) $ (31,776)
[1] For the year ended March 31, 2020, restructuring includes $0.9 million of stock-based compensation expense related to restructuring activities.