Restructuring - Summary of Restructuring and Related Costs (Detail) - USD ($)
$ in Thousands
12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Restructuring Cost and Reserve [Line Items]    
Restructuring charges incurred during the period [1]   $ 44,692
One-time Termination Benefits [Member]    
Restructuring Cost and Reserve [Line Items]    
Restructuring charges incurred during the period   4,633
Amounts paid during the period $ (1,053) (3,580)
Balance, end of year   $ 1,053
[1] For the year ended March 31, 2020, restructuring includes $0.9 million of stock-based compensation expense related to restructuring activities.