Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (12,667)	$ (20,303)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	3,407	745
Depreciation and amortization	4,494	119
Deferred income tax benefit		(143)
Amortization of license fee revenue	(97)	(96)
Amortization of right of use assets	367	2,297
Impairment of long-term investment	9,413
Impairment of cryptocurrencies	989	844
Loss on issuance of convertible notes, common stock and warrants		6,155
Change in fair value of convertible notes		3,896
Change in fair value of warrant liability		2,869
Gain on deconsolidation of Tess		(1,139)
Impairment of intangible rights acquired		700
Reversal of registration rights penalty	(1,358)
Gain on extinguishment of accounts payable, other liabilities and accrued interest		(854)
Realized gain on sale/exchange of cryptocurrencies	(5,184)	(665)
Gain on sale of equipment	(29)
Accrued interest on Verady investment		(20)
Changes in assets and liabilities:
Prepaid expenses and other current assets	795	(101)
Cryptocurrencies - mining, net of mining pool operating fees	(11,838)	(6,606)
Accounts payable and accrued expenses	929	(817)
Lease liability	(368)	(2,296)
Net cash used in operating activities	(11,147)	(15,415)
Cash flows from investing activities
Proceeds from sale of cryptocurrencies	8,298	3,196
Proceeds from sale of equipment	146
Deposits on equipment	(33,093)	(1,449)
Purchases of property and equipment	(8,139)	(4,958)
Patent costs incurred	(44)	(38)
Net cash used in investing activities	(32,832)	(3,249)
Cash flows from financing activities
Proceeds from issuance of convertible notes		3,000
Repayment of notes payable and other obligations		(950)
Proceeds from the issuance of common stock / At-the-market offering	264,727	24,825
Offering costs for the issuance of common stock / At-the-market offering	(7,255)	(996)
Proceeds from exercise of common stock warrants	2,895
Repurchase of common shares to pay employee withholding taxes	(446)
Net cash provided by financing activities	259,921	25,879
Net increase in cash and cash equivalents	215,942	7,215
Cash and cash equivalents at beginning of year	7,440	225
Cash and cash equivalents at end of year	223,382	7,440
Supplemental disclosure of cash flow information:
Cash paid for interest
Cash paid for taxes
Supplemental disclosure of noncash investing and financing activities:
Issuance of common stock to settle previously accrued executive compensation	175
Cryptocurrencies received from sale of equipment	52
Reclassification of deposits for miners	1,449
Conversion of notes payable to common stock		10,226
Reclassification of warrant liability to equity		5,439
Conversion of preferred stock to common stock		47
Common stock issued in connection with conversion of notes payable		255
Cryptocurrencies used to purchase miners		$ 99