Revenue from Contracts with Customers - Summary of Information about Receivables, Contract Assets and Contract Liabilities from Contracts with Customers (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Trade receivables	$ 153,638	$ 160,463
Current contract assets	7,398	6,832
Noncurrent contract assets	2,107	2,107
Current contract liabilities (deferred revenue)	(9,521)	(2,803)
Noncurrent contract liabilities (deferred revenue)	$ (25,023)	$ (17,723)

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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-Publisher FASB
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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.

+ References

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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