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Financial Instruments - Notional Values of Outstanding Foreign Exchange Forward Contracts, Foreign Exchange Option Contracts and Interest Rate Swap Contracts (Detail) - USD ($) $ in Thousands | Mar. 31, 2019 | Mar. 31, 2018
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Forward contracts (sell) [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | $ 444,757 | $ 449,371
Forward contracts (sell) [member] | US Dollars [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 230,292 | 242,418
Forward contracts (sell) [member] | UK Pound Sterling [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 134,077 | 132,591
Forward contracts (sell) [member] | Euro [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 34,251 | 23,883
Forward contracts (sell) [member] | Australian Dollars [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 43,271 | 48,147
Forward contracts (sell) [member] | Others Currencies [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 2,866 | 2,332
Option contracts (sell) [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 330,769 | 275,268
Option contracts (sell) [member] | US Dollars [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 134,060 | 107,629
Option contracts (sell) [member] | UK Pound Sterling [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 122,377 | 116,401
Option contracts (sell) [member] | Euro [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 32,226 | 21,483
Option contracts (sell) [member] | Australian Dollars [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | 42,106 | 28,828
Option contracts (sell) [member] | Others Currencies [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount |  | 927
Interest rate swap contracts [member] | US Dollars [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Derivative, notional amount | $ 61,800 | $ 89,900

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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