Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Summary of Pre-tax income in jurisdictions
Pre-tax income	$ (717)	$ 4,084	$ 2,881	$ 9,431
PRC [Member]
Summary of Pre-tax income in jurisdictions
Pre-tax income	(714)	4,084	2,891	9,445
Others [Member]
Summary of Pre-tax income in jurisdictions
Pre-tax income	$ (3)		$ (10)	$ (14)

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration