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

Long-Term Debt - Schedule of Senior Notes Redemption Prices Expressed as Percentages of Principal Amount (Detail)

v3.7.0.1
Long-Term Debt - Schedule of Senior Notes Redemption Prices Expressed as Percentages of Principal Amount (Detail) - Senior Unsecured Notes Due 15 February 2023 [Member]
 12 Months Ended
Mar. 31, 2017
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 101.00%
2018 [Member]  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 104.406%
2019 [Member]  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 102.938%
2020 [Member]  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 101.469%
2021 and thereafter [Member]  
Debt Instrument, Redemption [Line Items]  
Redemption price, percentage 100.00%