Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Summary of Pre-tax income in jurisdictions
Pre-tax income	$ 16,382	$ 17,870
Others [Member]
Summary of Pre-tax income in jurisdictions
Pre-tax income	(20)	(10)
PRC [Member]
Summary of Pre-tax income in jurisdictions
Pre-tax income	16,384	17,881
BVI [Member]
Summary of Pre-tax income in jurisdictions
Pre-tax income	$ 18	$ (1)

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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Period Type:	duration