Related Party Transactions - Sales and Purchases To and From Related Parties (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Related Party Transaction [Line Items]
Sales	$ 232	$ 1,687	$ 1,870	$ 4,358
Cost of revenue	190	1,478	1,427	3,677
Interest expense	100	100	300	300
Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
Sales	232	1,687	1,870	4,358
Cost of revenue	190	1,478	1,427	3,677
Manufacturing (cost of revenue)	308	287	925	974
Research and product development	153	140	447	453
Selling, marketing, general and administrative	966	786	2,984	2,954
Interest expense	104	112	349	338
Other expenses	84	89	255	234
DASAN \| Majority Shareholder \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
Sales	232	1,472	1,828	3,683
Cost of revenue	190	1,270	1,346	3,143
Selling, marketing, general and administrative	966	784	2,984	2,950
Interest expense	104	112	349	338
Other expenses	$ 84	$ 89	$ 255	$ 234
Tomato Soft Ltd. \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest	100.00%	100.00%	100.00%	100.00%
Manufacturing (cost of revenue)	$ 29	$ 27	$ 88	$ 84
Tomato Soft (Xi'an) Ltd. \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest	100.00%	100.00%	100.00%	100.00%
Manufacturing (cost of revenue)				$ 10
Research and product development	$ 137	$ 119	$ 392	$ 396
Chasan Networks Co., Ltd \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest	100.00%	100.00%	100.00%	100.00%
Manufacturing (cost of revenue)	$ 279	$ 260	$ 837	$ 880
Research and product development	$ 16	$ 21	$ 55	$ 57
Handysoft Inc \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest		17.63%		17.63%
Sales		$ 215		$ 473
Cost of revenue		208		357
Selling, marketing, general and administrative		$ 2		$ 4
J Mobile \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest	90.47%		90.47%
Sales			$ 42
Cost of revenue			$ 81
Dasan France \| Affiliated Entity \| Sales And Purchases To And From Related Parties
Related Party Transaction [Line Items]
DNI ownership interest		100.00%		100.00%
Sales				$ 202
Cost of revenue				$ 177

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Related party transaction, research and development expenses from transactions with related party.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of interest expense incurred on a debt or other obligation to related party.

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Amount of expense classified as other.

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Amount included in cost of sales related to transactions with related parties incurred and recorded in the statement of operations for the period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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