Stock Options: (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Options outstanding	8,582,952
Number of Shares, Options granted	300,000
Number of Shares, Less options forfeited	(280,418)
Number of Shares, Less options expired	0
Number of Shares, Less options exercised	0
Number of Shares, Options outstanding	8,602,534	8,582,952
Number of Shares, Options exercisable	6,004,722
Weighted-Average Exercise Price, Options outstanding	$ 1.32
Weighted-Average Exercise Price, Options granted	0.60
Weighted-Average Exercise Price, Less options forfeited	0.66
Weighted-Average Exercise Price, Less options expired	0.00
Weighted-Average Exercise Price, Less options exercised	0.00
Weighted-Average Exercise Price, Options outstanding	1.33	$ 1.32
Weighted-Average Exercise Price, Options exercisable	$ 1.40
Weighted-Average Remaining Contractual Term, Options outstanding (in years)	8 years	7 years 6 months
Weighted-Average Remaining Contractual Term, Options exercisable (in years)	7 years 4 months 24 days
Aggregate Intrinsic Value, Options outstanding	$ 0	$ 0
Aggregate Intrinsic Value, Options exercisable	$ 0