Accounts Receivable, Net and Revenue Concentrations - Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Accounts Receivable, Net, Current [Abstract]
Trade receivables, gross	$ 140,483	$ 142,299
Allowance for doubtful accounts	(1,008)	(1,064)	$ (950)	$ (904)
Allowance for sales returns	(596)	(562)
Net trade receivables	138,879	140,673
Other	4,783	10,905
Accounts receivable, net	$ 143,662	$ 151,578

Allowance for sales returns.

No definition available.

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- Definition

Amounts 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.

+ References

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- Definition

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.

+ References

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- References

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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- Definition

Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

+ References

No definition available.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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