Restructuring Charges (Details)	3 Months Ended	12 Months Ended
Jun. 30, 2016 USD ($) position	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Restructuring charge				$ 226,000
Beijing JiYa Semiconductor Material Co., Ltd
Number of workforce reduced \| position	28
Restructuring charge	$ 226,000	$ 0	$ 0

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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