Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flows From Operating Activities
Net loss	$ (1,709)	$ (4,549)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation		481
Stock-based compensation expense	949	2,227
Warrant modification expense		139
Loss on sale of business unit		127
Extinguishment of note payable	(1,275)
Amortization of note discount	1,091
(Gain) loss on sale of property and equipment	(82)	47
Change in operating assets and liabilities
Prepaid expenses and other current assets	52	(886)
Intangible digital assets	30	26
Right of use asset	18
Lease liability	(18)
Accounts payable	(174)	20
Accrued expenses	9	(551)
Net cash used in operating activities	(1,109)	(2,919)
Cash Flows From Investing Activities
Proceeds from sale of cybersecurity assets		60
Purchase of property and equipment		(6,987)
Proceeds from sale of property and equipment		427
Net cash used in investing activities		(6,500)
Cash Flows From Financing Activities
Proceeds from private placements of common stock		80
Proceeds from sale of stock under equity purchase agreement	1,457
Proceeds from sale of common stock warrants		281
Repayment of notes payable	(82)
Net cash provided by financing activities	1,375	361
Net change in cash and cash equivalents	266	(9,058)
Cash and cash equivalents, beginning of period	96	9,519
Cash and cash equivalents, end of period	362	461
Supplemental disclosure of cash flow information
Cash paid for interest	3
Cash paid for income tax
Non-cash investing and financing activities
Deemed dividend on trigger of down round provision		2,514
Stock issued for services not yet rendered		26
Repayment of note payable and interest through the issuance of shares under the equity purchase agreement	351
Cumulative effect adjustment related to ASU adoption	$ 3