Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Commitments and Contingencies - Additional Information (Detail)

v3.8.0.1
Commitments and Contingencies - Additional Information (Detail)
 12 Months Ended
Mar. 31, 2018
USD ($)
claim
Mar. 31, 2017
USD ($)
claim
Mar. 31, 2016
USD ($)
claim
Mar. 31, 2015
claim
Mar. 31, 2014
claim
Mar. 31, 2013
claim
Loss Contingencies [Line Items]            
Loss Contingency, Pending Claims, Number | claim 336 352 426 494 466 462
Net of estimated recoveries from third-party $ 900,000 $ 1,100,000        
Rental expense 20,600,000 $ 18,400,000 $ 16,900,000      
Acquisition of plant and equipment and other purchase obligations $ 0          
New Zealand [Member] | Subsidiaries [Member] | New Zealand Weathertightness [Member]            
Loss Contingencies [Line Items]            
Loss Contingency, Pending Claims, Number | claim     4