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)

v2.4.0.8
Employee Benefit Plans - Summary of Weighted Average Asset Allocation of Plan Assets by Asset Category (Detail)
12 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations 100.00% 100.00%
Equity Securities [Member]
   
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations Range Minimum 50.00%  
Target Plan Asset Allocations Range Maximum 70.00%  
Target Plan Asset Allocations 66.00% 68.00%
Debt Securities [Member]
   
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations Range Minimum 20.00%  
Target Plan Asset Allocations Range Maximum 50.00%  
Target Plan Asset Allocations 34.00% 32.00%
Other, including cash [Member]
   
Defined Benefit Plan Disclosure [Line Items]    
Target Plan Asset Allocations Range Minimum 0.00%  
Target Plan Asset Allocations Range Maximum 10.00%  
Target Plan Asset Allocations 0.00% 0.00%