CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 136,845	$ 395,474	$ 324,668	$ 454,601
Comprehensive gain	$ 136,845	$ 395,474	$ 324,668	$ 454,601

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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