Nature of Business and Operations (Details) - USD ($)	1 Months Ended			12 Months Ended
	Aug. 31, 2017	Mar. 31, 2017	Aug. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Nature of the Business and Operations (Textual)
Net loss (including noncontrolling interests)				$ (4,705,000)	$ (5,291,000)	$ (7,820,000)
Accumulated deficit				(183,745,000)	(179,040,000)
Net cash used in operating activities				(5,581,000)	(6,252,000)	(8,063,000)
Net proceeds from issuance of common stock				$ 9,079,000	$ 7,913,000	$ 5,422,000
Shelf registration statement, expire date		Mar. 24, 2020
Aggregate of common stock offering price		$ 20,000,000
Employee Investor Shares [Member]
Nature of the Business and Operations (Textual)
Issuance of common stock			427,352
Net proceeds from issuance of common stock			$ 500,000
Shares price per share			$ 1.17
Outside Investor Shares [Member]
Nature of the Business and Operations (Textual)
Issuance of common stock			4,600,000
Net proceeds from issuance of common stock			$ 4,600,000
Shares price per share			$ 1.00
Securities Purchase Agreement [Member]
Nature of the Business and Operations (Textual)
Issuance of common stock	9,750,000		8,627,352
Net proceeds from issuance of common stock	$ 9,100,000		$ 7,900,000
Shares price per share	$ 1.00
Warrant issued to purchase shares of common stock	3,250,001
Description of securities purchase agreement	The 2017 Warrants will become exercisable on August 8, 2018, and will expire on August 8, 2020.		(iii) up to 3,600,000 shares issuable upon exercise of warrants (the "Pre-Funded Warrants") by outside investors for which we received $3,564,000 pre-funded in proceeds and will receive up to $36,000 in proceeds upon future cash exercises.	The 2017 Warrants will become exercisable on August 8, 2018, and will expire on August 8, 2020.
Shelf registration statement, expire date					Feb. 17, 2022
Warrants expiration, date			Feb. 17, 2022
Proceeds from issuance of warrants	$ 9,750,000		$ 4,800,000	$ 6,500,000
Securities Purchase Agreement [Member] | Investor [Member]
Nature of the Business and Operations (Textual)
Proceeds from issuance of warrants	6,500,000
Purchase Warrants [Member]
Nature of the Business and Operations (Textual)
Issuance of common stock			4,313,676
Shares price per share			$ 1.12
Proceeds from issuance of warrants	$ 11,300,000		$ 11,300,000