Fair Value Measurements - Schedule of Financial Instruments Outstanding Measured at Fair Value on Recurring and Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Recurring
Forward contracts, liability	$ (2,000)
Carrying Amount [Member]
Recurring
Forward contracts	1,680	$ (6,734)
Non-recurring
Debt	(536,977)	(752,520)
Fair value [Member]
Recurring
Forward contracts, asset	1,680
Forward contracts, liability		(6,734)
Non-recurring
Debt	(558,077)	(777,072)
Level 2 [Member]
Recurring
Forward contracts, asset	1,680
Forward contracts, liability		(6,734)
Non-recurring
Debt	(515,735)	(728,072)
Level 3 [Member]
Non-recurring
Debt	$ (42,342)	$ (49,000)

Financial instruments measured at fair value on non-recurring basis.

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Financial instruments measured at fair value on recurring basis.

+ References

No definition available.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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