Loans receivable (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Notes and Loans Receivable Gross	$ 10,840,811	$ 12,602,473
Less current portion	1,812,532	1,843,600
Loans receivable, excluding current portion	9,028,279	10,758,873
Two loans originally aggregating $10,996,290, bearing interest at 6.5% per annum, receivable in monthly installments of $124,827 to May 2019, and secured by the machinery and equipment of the North Side Water Works plant [Member]
Notes and Loans Receivable Gross	7,925,386	8,798,106
Two loans originally aggregating $1,738,000, bearing interest at 5% per annum, receivable in monthly installments of $24,565 to March 2014, and secured by the machinery and equipment of the North Sound plant [Member]
Notes and Loans Receivable Gross	356,474	626,070
Two loans originally aggregating $3,671,039, bearing interest at 6.5% per annum, receivable in monthly installments of $54,513 to June 2017, and secured by the machinery and equipment of the Red Gate plant [Member]
Notes and Loans Receivable Gross	2,546,325	3,018,190
Two loans originally aggregating $897,000, bearing interest at 5% per annum, receivable in monthly installments of $12,678 to January 2013, and secured by the machinery and equipment of the Lower Valley plant [Member]
Notes and Loans Receivable Gross	$ 12,626	$ 160,107