Accounts receivable

12 Months Ended

Dec. 31, 2016

Receivables [Abstract]

Loans, Notes, Trade and Other Receivables Disclosure [Text Block]

4. Accounts receivable

	December 31
	2016		2015
Trade accounts receivable	$	15,368,218	$	8,235,514
Receivable - construction project		-		521,250
Receivable from OC-BVI		53,970		45,118
Other accounts receivable		1,271,948		920,472
		16,694,136		9,722,354
Allowance for doubtful accounts		(193,338)		(193,338)
	$	16,500,798	$	9,529,016

The activity for the allowance for doubtful accounts consisted of:

	December 31
	2016		2015
Opening allowance for doubtful accounts	$	193,338	$	193,338
Provision for doubtful accounts		42,553		-
Accounts written off during the year		(42,553)		-
Ending allowance for doubtful accounts	$	193,338	$	193,338

Significant concentrations of credit risk are disclosed in Note 21.