Revenue Recognition - Schedule of Information about Receivables, Contract Assets and Contract Liabilities from Contracts with Customers (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Revenue From Contract With Customer [Abstract]
Receivables	$ 16,609	$ 21,579
Short-term contract assets	697
Long-term contract assets	22
Short-term contract liabilities (deferred revenue)	2,622	2,064
Long-term contract liabilities (deferred revenue)	$ 56	$ 1,798

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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