Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans - Summary of Weighted Average Asset Allocation of Plan Assets by Asset Category (Detail)

v3.21.1
Employee Benefit Plans - Summary of Weighted Average Asset Allocation of Plan Assets by Asset Category (Detail)
Mar. 31, 2021
Mar. 31, 2020
Defined Benefit Plan Disclosure [Line Items]    
Weighted average asset allocation 100.00% 100.00%
Equity Securities [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations 30.00%  
Weighted average asset allocation 33.00% 30.00%
Debt Securities [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations 70.00%  
Weighted average asset allocation 67.00% 70.00%