COMPONENTS OF THE COMPANY'S CONSOLIDATED BALANCE SHEETS Components of Consolidated Balanec Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accounts Receivable
Accounts receivable trade	$ 58,718	$ 46,849
Accrued ship and debit	(39,486)	(38,075)
Allowance for stock rotation and rebate	(1,700)	(1,721)
Allowance for doubtful accounts	(734)	(525)
Total	16,798	6,528
Inventory, Net [Abstract]
Raw materials	15,517	14,610
Work-in-process	16,765	15,194
Finished goods	24,805	22,760
Total	57,087	52,564
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid income tax	460	2,431
Prepaid legal fees	213	212
Prepaid maintenance agreements	856	1,399
Advance to suppliers	1,211	69
Interest receivable	1,195	743
Other	3,823	3,861
Total	$ 7,758	$ 8,715

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Allowance for Stock Rotation and Rebate

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Prepaid Legal Fees

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Prepaid Maintenance Agreements

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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.

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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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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.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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