Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Cash Flows From Operating Activities
Net loss	$ (3,619)	$ (1,709)	$ (6,505)	$ (4,549)	$ (5,328)	$ (11,054)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation	0		708			1,189
Stock-based compensation expense					1,679	3,908
Warrant modification expense				139		139
Loss on sale of business unit						127
Extinguishment of note payable	(1,131)				(2,406)
Amortization of note discount	2,731		117		3,822	117
(Gain) loss on sale of property and equipment					(82)	47
Change in operating assets and liabilities
Prepaid expenses and other current assets					(220)	438
Intangible digital assets					(54)	(203)
Right of use asset					36
Lease liability					(37)
Other assets					4	(368)
Accounts payable					(46)	(223)
Accrued expenses					83	566
Net cash used in operating activities					(2,549)	(5,317)
Cash Flows From Investing Activities
Proceeds from sale of cybersecurity assets						60
Purchase of property and equipment					(72)	(6,994)
Proceeds from sale of property and equipment						427
Net cash used in investing activities					(72)	(6,507)
Cash Flows From Financing Activities
Proceeds from sale of common stock					525	80
Payment of deferred offering costs					(70)	(83)
Proceeds from the issuance of notes payable, net of original issue discount						3,700
Proceeds from sale of stock under equity purchase agreement, net of issuance costs					3,329
Sale of preferred stock, net of issuance costs					1,890
Repayment of notes payable					(210)
Proceeds from exercise of warrants					120	906
Net cash provided by financing activities					5,584	4,603
Net change in cash and cash equivalents					2,963	(7,221)
Cash and cash equivalents, beginning of period		$ 96		$ 9,519	96	9,519	$ 9,519
Cash and cash equivalents, end of period	$ 3,059		$ 2,298		3,059	2,298	$ 96
Supplemental disclosure of cash flow information
Cash paid for interest
Cash paid for income tax
Non-cash investing and financing activities
Deemed dividend on warrant modification and beneficial conversion feature of preferred stock					959
Deemed dividend on triger of down round provision						2,514
Stock issued for services not yet rendered						15
Cumulative effect adjustment related to ASU adoption					3
Conversion of notes payable into common stock					1,697
Repayment of note payable and interest through the issuance of shares under the equity purchase agreement					354
Non-cash deferred offering costs					62
Conversion of Series C convertible preferred stock into common stock					$ 14