Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Paid-In Capital [Member]	Accumulated Other Comprehensive (Loss) Gain [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2015	$ 5	$ 258,096	$ (67)	$ (217,297)	$ (258)	$ 40,479
Balance, shares at Dec. 31, 2015	4,522,186
Net loss			(19,605)			(19,605)
Common stock issued, net of issuance costs	$ 9	13,940				13,949
Common stock issued, net of issuance costs, shares	8,930,061
Common stock issued for extinguishment of convertible debt	$ 3	5,820				5,823
Common stock issued for extinguishment of convertible debt, shares	2,487,562
Common stock issued for settlement of accounts payable		850				850
Common stock issued for settlement of accounts payable, shares	214,991
Common stock issued for purchase of lithium properties		132				132
Common stock issued for purchase of lithium properties, shares	100,000
Common stock issued for loan interest		304				304
Common stock issued for loan interest, shares	83,000
Common stock issued for commitment fees		856				856
Common stock issued for commitment fees, shares	315,000
Stock compensation expense and related share issuances, net of shares withheld for the payment of taxes		195				195
Stock compensation expense and related share issuances, net of shares withheld for the payment of taxes, shares	14,594
Minimum withholding taxes on net share settlements of equity awards		(2)				(2)
Unrealized holding loss on marketable securities			67			67
Balance at Dec. 31, 2016	$ 17	280,191		(236,902)	(258)	43,048
Balance, shares at Dec. 31, 2016	16,667,394
Net loss				(19,288)		(19,288)
Common stock issued, net of issuance costs	$ 10	15,311				15,321
Common stock issued, net of issuance costs, shares	9,926,396
Common stock issued for settlement of accounts payable		325				325
Common stock issued for settlement of accounts payable, shares	177,700
Common stock issued for purchase of lithium properties		110				110
Common stock issued for purchase of lithium properties, shares	100,000
Common stock issued for loan interest
Common stock issued for commitment fees	$ 1	1,213				1,214
Common stock issued for commitment fees, shares	880,000
Stock compensation expense and related share issuances, net of shares withheld for the payment of taxes		101				101
Stock compensation expense and related share issuances, net of shares withheld for the payment of taxes, shares	38,834
Minimum withholding taxes on net share settlements of equity awards		(1)				(1)
Unrealized holding loss on marketable securities			287			287
Balance at Dec. 31, 2017	$ 28	$ 297,250	$ 287	$ (256,190)	$ (258)	$ 41,117
Balance, shares at Dec. 31, 2017	27,790,324