Business Acquisition - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
Jul. 31, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Lease expiration date		Dec. 31, 2028
ERIS Technology Corporation
Business Acquisition [Line Items]
Ownership percentage in subsidiary	51.00%
ERIS Technology Corporation \| Yea Shin Technology Co Ltd
Business Acquisition [Line Items]
Percentage of shares acquired by subsidiary in acquiree	51.00%
Outstanding shares acquired by subsidiary in cash	$ 6,400
ERIS Technology Corporation \| Yong Xiang Development Corporation
Business Acquisition [Line Items]
Total purchase price for business acquisition	25,500
Lease monthly payment for first 8.5 months	40
Lease monthly payment for the remaining period	30
Total lease commitment	$ 1,100
Lease expiration date	Dec. 31, 2020

Business combination cash consideration payable upon acquisition agreement.

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Operating leases future minimum payments due in first eight point five months.

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Operating leases future minimum payments due in remaining months.

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- Definition

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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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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