v3.8.0.1

Financial Instruments and Fair Value Measurements - Schedule of Fair Value and Classification of Derivative Instruments (Detail) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Derivatives Fair Value [Line Items] |  |
Asset | $ 20,310 | $ 47,114
Liability | 29,794 | 1,268
Forwards and Options [Member] | GBP [Member] |  |
Derivatives Fair Value [Line Items] |  |
Asset | 4,932 | 16,985
Liability | 7,158 | 0
Forwards and Options [Member] | CAD |  |
Derivatives Fair Value [Line Items] |  |
Asset | 0 | 831
Liability | 1,709 | 197
Forwards and Options [Member] | EUR |  |
Derivatives Fair Value [Line Items] |  |
Asset | 0 | 10,933
Liability | 12,144 | 0
Forwards and Options [Member] | JPY |  |
Derivatives Fair Value [Line Items] |  |
Asset | 6,671 | 9,246
Liability | 1,100 | 1,071
Interest Rate Hedges [Member] |  |
Derivatives Fair Value [Line Items] |  |
Asset | 8,707 | 435
Liability | 0 | 0
Net Investment Hedges [Member] | GBP [Member] |  |
Derivatives Fair Value [Line Items] |  |
Asset | 0 | 7,439
Liability | 0 | 0
Net Investment Hedges [Member] | CAD |  |
Derivatives Fair Value [Line Items] |  |
Asset | 0 | 1,245
Liability | $ 7,683 | $ 0

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