Options and warrants (Details 1)	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Shares
Outstanding Shares, Beginning Balance | shares	4,600,000
Options and warrants granted | shares	1,050,000
Options and warrants cancelled or expired | shares	40,000
Outstanding Shares, Ending Balance | shares	5,610,000
Exercisable Shares | shares	5,110,000
Weighted Average Exercise
Outstanding, Beginning Balance | $ / shares	$ 0.22
Options and warrants granted | $ / shares	0.18
Options and warrants cancelled or expired | $ / shares	6.00
Outstanding, Ending Balance | $ / shares	0.17
Exercisable | $ / shares	$ 0.17
Weighted Average Remaining Contractual Life
Outstanding life	4 years 5 months 16 days
Outstanding life	3 years 7 months 13 days
Exercisable	3 years 6 months 26 days
Aggregate Intrinsic Value
Outstanding value | $
Options and warrants granted | shares
Options and warrants cancelled or expired | $ / shares
Outstanding value | $	$ 440,000
Exercisable | $	$ 400,000