Intangible Assets, Net (Tables)

3 Months Ended

Mar. 31, 2019

Intangible Assets, net [Abstract]

Schedule of intangible assets

	December 31,			March 31,
	2018			2019
Computer software at cost	$	31,025		$	31,797
Accumulated amortization		(10,156	)		(11,992	)
	$	20,869		$	19,805