Summary of Significant Accounting Policies - Revenue Recognition - Condensed Statement of Cash flows (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net loss	$ (1,277)	$ (6,086)
Adjustments to reconcile net loss to net cash used in operating activities:
Accounts receivable	(5,810)	513
Inventory	888	(755)
Deferred income on shipments to distributors	(39)	$ (357)
ASU 2014-09 \| Balances without the adoption of Topic 606
Cash flows from operating activities
Net loss	(1,785)
Adjustments to reconcile net loss to net cash used in operating activities:
Accounts receivable	(5,838)
Inventory	908
Deferred income on shipments to distributors	477
ASU 2014-09 \| Adjustments
Cash flows from operating activities
Net loss	(508)
Adjustments to reconcile net loss to net cash used in operating activities:
Accounts receivable	(28)
Inventory	20
Deferred income on shipments to distributors	$ 516

The increase (decrease) during the reporting period in customer liability.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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