CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)	Total	Redeemable preferred stock [Member]	Common stock [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Cumulative translation adjustment [Member]	Non-controlling interests [Member]
Balance at Dec. 31, 2016	$ 154,105,372	$ 21,135	$ 8,922,998	$ 85,621,033	$ 51,589,337	$ (549,555)	$ 8,500,424
Balance (in shares) at Dec. 31, 2016		35,225	14,871,664
Issue of share capital	210,151	$ 5,665	$ 20,995	183,491	0	0	0
Issue of share capital (in shares)		9,441	34,991
Conversion of preferred stock	0	$ (7,328)	$ 7,328	0	0	0	0
Conversion of preferred stock (in shares)		(12,214)	12,214
Buyback of preferred stock	(9,719)	$ (656)	$ 0	(9,063)	0	0	0
Buyback of preferred stock (in shares)		(1,093)	0
Net income	5,732,573	$ 0	$ 0	0	6,144,062	0	(411,489)
Exercise of options	17,777	$ 1,277	$ 0	16,500	0	0	0
Exercise of options (in shares)		2,129	0
Dividends declared	(4,628,203)	$ 0	$ 0	0	(4,628,203)	0	0
Stock-based compensation	593,426	0	0	593,426	0	0	0
Balance at Dec. 31, 2017	156,021,377	$ 20,093	$ 8,951,321	86,405,387	53,105,196	(549,555)	8,088,935
Balance (in shares) at Dec. 31, 2017		33,488	14,918,869
Issue of share capital	236,691	$ 4,445	$ 34,938	197,308	0	0	0
Issue of share capital (in shares)		7,409	58,228
Conversion of preferred stock	0	$ (3,485)	$ 3,485	0	0	0	0
Conversion of preferred stock (in shares)		(5,809)	5,809
Buyback of preferred stock	(17,338)	$ (976)	$ 0	(16,362)	0	0	0
Buyback of preferred stock (in shares)		(1,627)	0
Net income	11,989,274	$ 0	$ 0	0	11,293,487	0	695,787
Exercise of options	12,976	$ 801	$ 0	12,175	0	0	0
Exercise of options (in shares)		1,335	0
Dividends declared	(5,100,522)	$ 0	$ 0	0	(5,100,522)	0	0
Stock-based compensation	613,445	0	0	613,445	0	0	0
Balance at Dec. 31, 2018	$ 163,755,903	$ 20,878	$ 8,989,744	$ 87,211,953	$ 59,298,161	$ (549,555)	$ 8,784,722
Balance (in shares) at Dec. 31, 2018		34,796	14,982,906