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

Derivative Instruments - Additional Information (Detail)

v3.7.0.1
Derivative Instruments - Additional Information (Detail) - USD ($)
12 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2015
Derivative [Line Items]      
Notional amount of interest rate swap contracts $ 100,000,000 $ 100,400,000  
Derivative weighted average fixed interest rate 2.10%    
Weighted average remaining life of contracts 2 years 4 months 24 days    
Interest rate swap contracts included in Accounts Payable $ 1,100,000 3,700,000  
Unrealized gain (loss) on interest rate swap contracts 2,600,000 (600,000) $ (2,600,000)
Realized loss on interest rate swap contracts (1,300,000) (1,900,000) $ (1,300,000)
Derivatives Not Accounted for As Hedges [Member] | Cash Flow Hedging [Member]      
Derivative [Line Items]      
Unrealized gain associated with the forward contracts not designated as a cash flow hedging arrangement 0 900,000  
Interest Rate Swap Contracts [Member]      
Derivative [Line Items]      
Interest rate swap contracts included in Accounts Payable 1,100,000 3,700,000  
Interest Rate Swap Contracts [Member] | Derivatives Not Accounted for As Hedges [Member]      
Derivative [Line Items]      
Notional amount of interest rate swap contracts 100,000,000 100,000,000  
Interest rate swap contracts included in Accounts Payable $ 1,100,000 $ 3,700,000