Certain Balance Sheet Accounts - Summary of Non-current Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Deferred tax liability	$ 97	$ 852
Deferred rent	6,501us-gaap_DeferredRentCreditNoncurrent	6,678us-gaap_DeferredRentCreditNoncurrent
Other	2,810us-gaap_OtherLiabilitiesNoncurrent	2,612us-gaap_OtherLiabilitiesNoncurrent
Total non-current liabilities	$ 9,408us-gaap_LiabilitiesNoncurrent	$ 10,142us-gaap_LiabilitiesNoncurrent

For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 25

-Paragraph 2

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Amount of deferred tax liability attributable to taxable temporary differences, net of deferred tax asset attributable to deductible temporary differences and carryforwards net of valuation allowances expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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

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-Name Accounting Standards Codification

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Amount of obligation due after one year or beyond the normal operating cycle, if longer.

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

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-Name Accounting Standards Codification

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Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

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

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