Shareholders' Equity Stock options and warrants (Details) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Stock Options and Warrants [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 580,900		$ 1,658,100
Common Stock Warrants, Shares	3,555,956		4,898,266
Weighted Average Exercise Price, Warrants Outstanding	14.13		16.50
Weighted Average Remaining Contractual Term warrant outstanding	2 years 4 months 13 days		2 years 7 months 17 days
Aggregate Intrinsic Value, Warrants Outstanding	273,200		1,811,000
Warrants Granted	2,722
Warrants Granted	0	20,407
Weighted Average Exercise Price, Warrants Granted	$ 12.26
Warrants Exercised	(333,250)
Weighted Average Exercise Price, Warrants Exercised	$ 5.16
Warrants Expired	(100,108)
Weighted Average Exercise Price, Warrants Expired	$ 70.00
Warrants Canceled	(911,674)
Weighted Average Exercise Price, Warrants Canceled	$ 23.97
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value	561,200
shares, vested and expected to vest	3,555,956
Weighted Average Exercise Price, Warrants vested & expected to vest	14.13
Aggregate Intrinsic Value, Warrants vested and expected to vest	273,200
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value	403,900
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	3,545,956
Weighted Average Exercise Price, Warrants Exercisable	14.15
weighted Average Remaining Contractual Term, warrants vested	2 years 4 months 13 days
Aggregate Intrinsic Value, Warrants vested	273,200
Stock and Warrants Issued During Period, Value, Preferred Stock and Warrants	$ 0	$ 70,500
US Equity Plan [Member]
Stock Options and Warrants [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	4,459,923		2,932,191
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 9.24		$ 11.19
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	7 years 6 months 22 days		6 years 9 months 22 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	2,102,525
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 6.85
Stock Options Exercised	(48,987)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 5.53
Stock Options Expired	(262,954)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price	$ 6.54
Stock Options Forfeited	(262,852)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price	$ 15.18
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	4,172,772
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 9.38
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term	7 years 5 months 9 days
Weighted Average Remaining Contractual Term, Warrants Vested and Expect to Vest	2 years 4 months 13 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	2,823,720
Weighted average estimated fair value of shares granted	$ 10.36
Options, Vested, weighted Average Remaining Contractual Term	6 years 8 months 23 days
Minimum [Member]
Stock Options and Warrants [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	$ 5.20
Maximum [Member]
Stock Options and Warrants [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	$ 6.20