Assets and Liabilities Measured at Fair Value (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value Assets
Total marketable securities	$ 63,347	$ 126,052
Foreign currency forward contracts
Fair Value Liabilities
Foreign currency forward contracts	393	1,052
Fair Value Assets
Foreign currency forward contracts	354	48
Money Market Funds
Fair Value Assets
Money market funds	481	573
Municipal bonds
Fair Value Assets
Total marketable securities	35,727	57,335
Corporate bonds
Fair Value Assets
Total marketable securities	26,669	66,815
Certificates of Deposit
Fair Value Assets
Total marketable securities	951	1,902
Level 1 \| Money Market Funds
Fair Value Assets
Money market funds	481	573
Level 2
Fair Value Assets
Total marketable securities	63,347	126,052
Level 2 \| Foreign currency forward contracts
Fair Value Liabilities
Foreign currency forward contracts	393	1,052
Fair Value Assets
Foreign currency forward contracts	354	48
Level 2 \| Municipal bonds
Fair Value Assets
Total marketable securities	35,727	57,335
Level 2 \| Corporate bonds
Fair Value Assets
Total marketable securities	26,669	66,815
Level 2 \| Certificates of Deposit
Fair Value Assets
Total marketable securities	$ 951	$ 1,902

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-Topic 320
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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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.

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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.

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