Income Taxes - Summary of Activity Related to Gross Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Income Tax Disclosure [Abstract]
Balance as of January 1, 2013	$ 3,019
Increases related to prior year tax positions
Decreases related to prior year tax positions
Increases related to current year tax positions
Decreases related to current year tax positions
Effect of exchange rate changes	(245)
Balance as of September 30, 2013	$ 2,774

Effect of exchange rate changes.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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