Summary of Significant Accounting Policies (Details) - USD ($) shares in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of Significant Accounting Policies [Abstract]
Foreign exchange gain	$ 200,000		$ 100,000
Changes in carrying amounts of warrant liabilities [Abstract]
Beginning balance	693,457	$ 5,131,000
Issued	6,933,000	0
Exercised	(9,000)	0
Net changes in valuation	(3,828,000)	(4,438,000)
Ending balance	$ 3,789,391	$ 693,457	$ 5,131,000
Antidilutive securities excluded from computation of earning per share amount (in shares)	50.0	21.4	17.4
Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents	$ 56,276,000	$ 20,673,000
Short-term investments		35,035,000
Warrant liabilities	$ (3,789,000)	(693,000)
Minimum [Member]
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Useful life	5 years
Level I [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents	$ 56,276,000	20,673,000
Short-term investments		35,035,000
Warrant liabilities	0	0
Level II [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents	0	0
Short-term investments		0
Warrant liabilities	0	0
Level III [Member] | Recurring [Member]
Fair value measurements by level for assets and liabilities measured at fair value on a recurring basis
Cash equivalents	0	0
Short-term investments		0
Warrant liabilities	$ (3,789,000)	$ (693,000)