Assets and Liabilities Measured at Fair Value (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets
Total marketable securities	$ 63,167	$ 126,052
Foreign currency forward contracts
Fair Value Liabilities
Foreign currency forward contracts	883	1,052
Fair Value Assets
Foreign currency forward contracts	628	48
Money Market Funds
Fair Value Assets
Money market funds	458	573
Municipal bonds
Fair Value Assets
Total marketable securities	36,607	57,335
Corporate bonds
Fair Value Assets
Total marketable securities	26,560	66,815
Certificates of Deposit
Fair Value Assets
Total marketable securities		1,902
Level 1 \| Money Market Funds
Fair Value Assets
Money market funds	458	573
Level 2
Fair Value Assets
Total marketable securities	63,167	126,052
Level 2 \| Foreign currency forward contracts
Fair Value Liabilities
Foreign currency forward contracts	883	1,052
Fair Value Assets
Foreign currency forward contracts	628	48
Level 2 \| Municipal bonds
Fair Value Assets
Total marketable securities	36,607	57,335
Level 2 \| Corporate bonds
Fair Value Assets
Total marketable securities	$ 26,560	66,815
Level 2 \| Certificates of Deposit
Fair Value Assets
Total marketable securities		$ 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
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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
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-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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