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, 2013	$ 141,498,373	$ 22,445	$ 8,811,718	$ 83,381,387	$ 47,155,548	$ (471,983)	$ 2,599,258
Balance (in shares) at Dec. 31, 2013		37,408	14,686,197
Issue of share capital	259,337	$ 3,574	$ 10,976	244,787	0	0	0
Issue of share capital (in shares)		5,957	18,294
Conversion of preferred stock	0	$ (2,854)	$ 2,854	0	0	0	0
Conversion of preferred stock (in shares)		(4,756)	4,756
Buyback of preferred stock	(13,662)	$ (1,093)	$ 0	(12,569)	0	0	0
Buyback of preferred stock (in shares)		(1,822)	0
Net income	6,764,540	$ 0	$ 0	0	6,265,358	0	499,182
Exercise of options	53,136	$ 32	$ 3,991	49,113	0	0	0
Exercise of options (in shares)		53	6,652
Dividends declared	(4,584,681)	$ 0	$ 0	0	(4,420,285)	0	(164,396)
Foreign currency translation adjustment	(10,953)	0	0	0	0	(10,405)	(548)
Stock-based compensation	116,574	0	0	116,574	0	0	0
Balance at Dec. 31, 2014	144,082,664	$ 22,104	$ 8,829,539	83,779,292	49,000,621	(482,388)	2,933,496
Balance (in shares) at Dec. 31, 2014		36,840	14,715,899
Issue of share capital	143,218	$ 5,169	$ 6,308	131,741	0	0	0
Issue of share capital (in shares)		8,615	10,514
Conversion of preferred stock	0	$ (4,317)	$ 4,317	0	0	0	0
Conversion of preferred stock (in shares)		(7,195)	7,195
Buyback of preferred stock	(6,014)	$ (449)	$ 0	(5,565)	0	0	0
Buyback of preferred stock (in shares)		(748)	0
Net income	7,925,494	$ 0	$ 0	0	7,518,701	0	406,793
Exercise of options	456,763	$ 775	$ 28,557	427,431	0	0	0
Exercise of options (in shares)		1,292	47,593
Dividends declared	(4,617,810)	$ 0	$ 0	0	(4,435,147)	0	(182,663)
Foreign currency translation adjustment	(53,660)	0	0	0	0	(50,977)	(2,683)
Stock-based compensation	264,450	0	0	264,450	0	0	0
Balance at Dec. 31, 2015	148,195,105	$ 23,282	$ 8,868,721	84,597,349	52,084,175	(533,365)	3,154,943
Balance (in shares) at Dec. 31, 2015		38,804	14,781,201
Issue of share capital	179,573	$ 5,053	$ 15,094	159,426	0	0	0
Issue of share capital (in shares)		8,421	25,156
Conversion of preferred stock	0	$ (6,935)	$ 6,935	0	0	0	0
Conversion of preferred stock (in shares)		(11,558)	11,558
Buyback of preferred stock	(14,054)	$ (1,053)	$ 0	(13,001)	0	0	0
Buyback of preferred stock (in shares)		(1,755)	0
Net income	2,777,313	$ 0	$ 0	0	3,960,501	0	(1,183,188)
Exercise of options	568,849	$ 788	$ 32,248	535,813	0	0	0
Exercise of options (in shares)		1,313	53,749
Dividends declared	(4,638,002)	$ 0	$ 0	0	(4,455,339)	0	(182,663)
Foreign currency translation adjustment	(17,042)	0	0	0	0	(16,190)	(852)
Beginning Aerex non-controlling interest at fair value	6,712,184						6,712,184
Stock-based compensation	341,446	0	0	341,446	0	0	0
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