Summary of Long-Term Debt Outstanding (Parenthetical) (Detail)	12 Months Ended
	Mar. 31, 2016
4.61% July 2003 Senior Notes Due Fiscal 2016
Debt [Line Items]
Debt instrument interest rate	4.61%
Debt Instrument Maturity Period	2016
3.28% September 2010 Senior Notes Due Fiscal 2016
Debt [Line Items]
Debt instrument interest rate	3.28%
Debt Instrument Maturity Period	2016
3.90% September 2010 Senior Notes Due Fiscal 2018
Debt [Line Items]
Debt instrument interest rate	3.90%
Debt Instrument Maturity Period	2018
3.95% September 2010 Senior Notes Due Fiscal 2018
Debt [Line Items]
Debt instrument interest rate	3.95%
Debt Instrument Maturity Period	2018
4.12% September 2010 Senior Notes Due Fiscal 2019
Debt [Line Items]
Debt instrument interest rate	4.12%
Debt Instrument Maturity Period	2019
4.17% September 2010 Senior Notes Due Fiscal 2019
Debt [Line Items]
Debt instrument interest rate	4.17%
Debt Instrument Maturity Period	2019
4.33% September 2010 Senior Notes Due Fiscal 2020
Debt [Line Items]
Debt instrument interest rate	4.33%
Debt Instrument Maturity Period	2020
4.51% September 2010 Senior Notes Due Fiscal 2021
Debt [Line Items]
Debt instrument interest rate	4.51%
Debt Instrument Maturity Period	2021
4.56% September 2010 Senior Notes Due Fiscal 2021
Debt [Line Items]
Debt instrument interest rate	4.56%
Debt Instrument Maturity Period	2021
4.61% September 2010 Senior Notes Due Fiscal 2023
Debt [Line Items]
Debt instrument interest rate	4.61%
Debt Instrument Maturity Period	2023
4.06% August 2011 Senior Notes Due Fiscal 2019
Debt [Line Items]
Debt instrument interest rate	4.06%
Debt Instrument Maturity Period	2019
4.54% August 2011 Senior Notes Due Fiscal 2022
Debt [Line Items]
Debt instrument interest rate	4.54%
Debt Instrument Maturity Period	2022
4.64% August 2011 Senior Notes Due Fiscal 2022
Debt [Line Items]
Debt instrument interest rate	4.64%
Debt Instrument Maturity Period	2022
4.26% September 2013 senior notes due fiscal 2021
Debt [Line Items]
Debt instrument interest rate	4.26%
Debt Instrument Maturity Period	2021
5.01% September 2013 senior notes due fiscal 2024
Debt [Line Items]
Debt instrument interest rate	5.01%
Debt Instrument Maturity Period	2024
5.16% September 2013 senior notes due fiscal 2026
Debt [Line Items]
Debt instrument interest rate	5.16%
Debt Instrument Maturity Period	2026
Norwegian Kroner Denominated Notes Due Fiscal Two Thousand Twenty Five
Debt [Line Items]
Debt Instrument Maturity Period	2025
Norwegian Kroner Denominated Notes Due Fiscal Two Thousand Twenty Six
Debt [Line Items]
Debt Instrument Maturity Period	2026
Norwegian Kroner Denominated Borrowing Agreement Due Fiscal Two Thousand Sixteen
Debt [Line Items]
Debt Instrument Maturity Period	2016
Norwegian Kroner Denominated Borrowing Agreement Due Fiscal Two Thousand Nineteen
Debt [Line Items]
Debt Instrument Maturity Period	2019
United States Dollar Denominated Borrowing Agreement Due Fiscal Two Thousand Twenty Seven
Debt [Line Items]
Debt Instrument Maturity Period	2027
United States Dollar Denominated Borrowing Agreement Due Fiscal Two Thousand Twenty Eight
Debt [Line Items]
Debt Instrument Maturity Period	2028
Term Loan Facility Due Twenty Twenty
Debt [Line Items]
Debt Instrument Maturity Period	2020
Revolving Line Of Credit Due Fiscal Twenty Twenty
Debt [Line Items]
Debt Instrument Maturity Period	2020