Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows From Operating Activities
Net loss	$ (4,549)	$ (5,891)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation	481	99
Amortization of intangible assets		42
Stock-based compensation expense	2,227	1,299
Warrant modification expense	139
Loss on sale of property and equipment	47
Loss on sale of cybersecurity assets	127
Impairment/loss on sale of investments		2,871
Accretion of debt discount		37
Change in operating assets and liabilities
Prepaid expenses and other current assets	(886)	33
Digital currencies	26	(9)
Accounts payable	20	263
Accrued expenses	(551)	72
Other payables		5
Net cash used in operating activities	(2,919)	(1,180)
Cash Flows From Investing Activities
Purchase of property and equipment	(6,987)
Proceeds from sale of cyber security unit	60
Proceeds from sale of property and equipment	427
Proceeds from sale of investments		26
Net cash (used in) provided by investing activities	(6,500)	26
Cash Flows From Financing Activities
Proceeds from private placements of common stock	80	650
Proceeds from issuance of convertible notes payable and warrants, net		493
Proceeds from exercise of warrants	281
Net cash provided by financing activities	361	1,143
Net change in cash and cash equivalents	(9,058)	(11)
Cash and cash equivalents, beginning of period	9,519	345
Cash and cash equivalents, end of period	461	334
Supplemental disclosure of cash flow information
Cash paid for interest		7
Cash paid for income tax
Non-cash investing and financing activities
Conversion of convertible debt and accrued interest		1,800
Issuance of L2 commitment note		160
Deemed dividend on trigger of down round provision	2,514
Reclassification adjustment upon sale of available for sale investment in net loss		66
Stock issued for services not yet rendered	$ 26