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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
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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%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph e -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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