Property, plant and equipment and construction in progress (Tables)

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment [Table Text Block]

	December 31,
	2016		2015
Land	$	3,570,361	$	3,223,361
Buildings		19,366,123		18,437,758
Plant and equipment		62,227,399		63,733,553
Distribution system		33,482,674		31,726,766
Office furniture, fixtures and equipment		3,405,633		3,210,819
Vehicles		1,396,886		1,384,294
Leasehold improvements		261,147		260,519
Lab equipment		151,233		157,851
		123,861,456		122,134,921
Less accumulated depreciation		70,777,351		68,391,751
Property, plant and equipment, net	$	53,084,105	$	53,743,170
Construction in progress	$	885,494	$	1,928,610