ParkerVision (PRKR) 10-K 31 Mar 21 2020 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 30, 2021	Jun. 30, 2020
Document And Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Document Transition Report	false
Entity File Number	000-22904
Entity Registrant Name	PARKERVISION INC
Entity Central Index Key	0000914139
Entity Incorporation, State or Country Code	FL
Entity Tax Identification Number	59-2971472
Entity Address, Address Line One	4446-1A Hendricks Avenue
Entity Address, Address Line Two	Suite 354
Entity Address, City or Town	Jacksonville
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	32207
City Area Code	904
Local Phone Number	732-6100
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Shell Company	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Public Float			$ 23,474,499
Entity Common Stock, Shares Outstanding		69,886,849
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
CURRENT ASSETS:
Cash and cash equivalents	$ 1,627	$ 57
Prepaid expenses	599	505
Other current assets	8	117
Total current assets	2,234	679
Property and equipment, net	30	70
Intangible assets, net	2,170	2,878
Operating lease right-of-use assets	10	283
Other assets, net	12	16
Total assets	4,456	3,926
CURRENT LIABILITIES:
Accounts payable	4,318	2,328
Accrued expenses:
Salaries and wages	19	78
Professional fees	128	499
Statutory court costs	251	369
Other accrued expenses	936	1,081
Related party note payable, current portion	100	86
Secured note payable, current portion	26	1,222
Unsecured notes payable	65	225
Operating lease liabilities, current portion	146	250
Total current liabilities	5,989	6,138
LONG-TERM LIABILITES:
Secured contingent payment obligation	33,057	26,651
Unsecured contingent payment obligations	5,222
Convertible notes, net	3,018	2,733
Related party note payable, net of current portion	703	793
Operating lease liabilities, net of current portion	159	305
Other long-term liabilities	129	403
Total long-term liabilities	42,288	30,885
Total liabilities	48,277	37,023
COMMITMENTS AND CONTINGENCIES
SHAREHOLDERS' DEFICIT:
Common stock, $.01 par value, 140,000 and 110,000 shares authorized, 58,591 and 34,097 issued and outstanding at December 31, 2020 and 2019, respectively	586	341
Additional paid-in capital	376,954	368,345
Accumulated deficit	(421,361)	(401,783)
Total shareholders' deficit	(43,821)	(33,097)
Total liabilities and shareholders' deficit	$ 4,456	$ 3,926

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Consolidated Balance Sheets [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	140,000,000	110,000,000
Common stock, shares issued	58,591,000	34,097,000
Common stock, shares outstanding	58,591,000	34,097,000

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Loss on impairment of inventory		$ 6
Gross margin		(5)
Research and development expenses		334
Selling, general and administrative expenses	10,664	7,602
Total operating expenses	10,664	7,936
Interest and other income		3
Interest and other expense	(547)	(421)
Change in fair value of contingent payment obligations	(8,367)	(1,094)
Total interest and other	(8,914)	(1,512)
Net loss before income tax	(19,578)	(9,453)
Income tax expense
Net loss	(19,578)	(9,453)
Other comprehensive income, net of tax
Comprehensive loss	$ (19,578)	$ (9,453)
Basic and diluted net loss per common share	$ (0.42)	$ (0.30)
Weighted average common shares outstanding	47,019	31,461
Product [Member]
Product revenue		$ 74
Cost of sales		$ 73

Consolidated Statements Of Shar

Consolidated Statements Of Shareholders' Deficit - USD ($) $ in Thousands	Common Stock [Member]Long-term Debt [Member]	Common Stock [Member]Short-term Debt [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]Long-term Debt [Member]	Additional Paid-in Capital [Member]Short-term Debt [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Deficit [Member]	Long-term Debt [Member]	Short-term Debt [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
Balance, value at Dec. 31, 2018			$ 287			$ 366,695	$ (38)	$ (392,292)			$ (38)	$ (25,310)
Issuance of common stock upon exercise of warrants			29									29
Issuance of common stock and warrants for services			6			234						240
Issuance of convertible debt with beneficial conversion feature						550						550
Issuance of common stock upon conversion	$ 19			$ 277					$ 296
Share-based compensation, net of shares withheld for taxes						589						589
Net loss for the year								(9,453)				(9,453)
Balance, value at Dec. 31, 2019			341			368,345		(401,783)				(33,097)
Issuance of common stock and warrants in private offerings, net of issuance costs			148			4,618						4,766
Issuance of common stock upon exercise of warrants			45			1,530						1,575
Issuance of common stock and warrants for services			7			297						304
Issuance of convertible debt with beneficial conversion feature						173						173
Issuance of common stock upon conversion	$ 15	$ 22		$ 437	$ 318				$ 452	$ 340
Share-based compensation, net of shares withheld for taxes			8			1,236						1,244
Net loss for the year								(19,578)				(19,578)
Balance, value at Dec. 31, 2020			$ 586			$ 376,954		$ (421,361)				$ (43,821)

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (19,578)	$ (9,453)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	632	835
Share-based compensation	1,244	589
Noncash lease expense	61	280
Change in fair value of contingent payment obligation	8,367	1,094
Loss on disposal/impairment of equipment and other assets	487	412
Noncash expense for amendment of equity-related agreements	2,211
Inventory impairment charges		6
Changes in operating assets and liabilities:
Accounts receivable		2
Finished goods inventories		81
Prepaid expenses and other assets	292	221
Accounts payable and accrued expenses	1,757	2,790
Operating lease liabilities	(250)	(230)
Total adjustments	14,801	6,080
Net cash used in operating activities	(4,777)	(3,373)
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sale of property and equipment	2	30
Purchases of property and equipment	(3)	(5)
Payments for patent costs and other intangible assets		(18)
Net cash (used in)/provided by investing activities	(1)	7
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock and contingent payment rights in private offerings	4,801
Net proceeds from exercise of warrants	1,575	29
Net proceeds from debt financings	1,244	3,068
Debt repayments	(1,272)	(1,200)
Principal payments on finance lease obligation		(1)
Net cash provided by financing activities	6,348	1,896
NET CHANGE IN CASH AND CASH EQUIVALENTS	1,570	(1,470)
CASH AND CASH EQUIVALENTS, beginning of year	57	1,527
CASH AND CASH EQUIVALENTS, end of year	1,627	57
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	61	4
Cash paid for income taxes

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Significant Accounting Policies	1. SIGNIFICANT ACCOUNTING POLICIES  ParkerVision, Inc. and its wholly-owned German subsidiary, ParkerVision GmbH (collectively “ParkerVision”, “we” or the “Company”) is in the business of innovating fundamental wireless hardware technologies and products. W e have determined that our business currently operates under a single operating and reportable segment .  We have designed and developed proprietary radio frequency (“ RF ”) technologies and integrated circuits for use in wireless communication products. We have expended significant financial and other resources to research and develop our RF technologies and to obtain patent protection for those technologies in the United States of America (“ U.S .”) and certain foreign jurisdictions. We believe certain patents protecting our proprietary technologies have been broadly infringed by others, and therefore the primary focus of our business plan is the enforcement of our intellectual property rights through patent infringement litigation and licensing efforts. We currently have patent enforcement actions ongoing in various U.S. district courts against providers of mobile handsets, smart televisions and other WiFi products and , in certain cases, their chip suppliers for the infringement of a number of our RF patents. We have made significant investments in developing and protecting our technologies, the returns on which are dependent upon the generation of future revenues for realization.  In 2018, we restructured our operations to reduce operating expenses. As part of that restructuring, we made significant reductions in our investment in the development and marketing of a consumer distributed WiFi product line marketed under the brand name Milo ® . In early 2019, we ceased substantially all ongoing research and development efforts and, where applicable, repurposed resources to support our patent enforcement and product sales and support efforts. We ceased sales of our Milo products in the fourth quarter of 2019 and are currently focused exclusively on our patent enforcement litigation and licensing efforts.  Basis of Presentation Our consolidated financial statements are prepared in accordance with generally accepted accounting principles in the U.S. (“ GAAP ”). Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The consolidated financial statements include the accounts of ParkerVision, Inc. and our wholly-owned German subsidiary, ParkerVision GmbH, after elimination of all intercompany transactions and accounts.  Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. The more significant estimates made by us include projected future cash flows and risk-adjusted discount rates for estimating the fair value of our contingent payment obligations, the volatility and estimated lives of share-based awards used in the estimate of the fair market value of share-based compensation, the assessment of recoverability of long-lived assets, the amortization periods for intangible and long-lived assets, and the valuation allowance for deferred taxes. Actual results could differ from the estimates made. We periodically evaluate estimates used in the preparation of the financial statements for continued reasonableness. Appropriate adjustments, if any, to the estimates used are made prospectively based upon such periodic evaluation. Cash and Cash Equivalents We consider cash and cash equivalents to include cash on hand, interest-bearing deposits, overnight repurchase agreements and investments with original maturities of three months or less when purchased.  Inventory Inventory is stated at the lower of actual cost, as determined under the first-in, first-out method, or estimated net realizable value. We review our inventory for estimated obsolescence or unmarketable inventory and write down inventory for the difference between cost and estimated market value based upon assumptions about future demand. Future demand is affected by market conditions, technological obsolescence, new products and strategic plans, each of which is subject to change. Due to the decision to discontinue Milo product sales in the fourth quarter of 2019, a full reserve was recorded against the remaining inventory on hand at December 31, 2019. All remaining inventory was disposed of during the year ended December 31, 2020.  Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is determined using the straight-line method over the following estimated useful lives:    Manufacturing and office equipment 5 -7 years  Leasehold improvements Shorter of useful life or remaining life of lease  Furniture and fixtures 7 years  Computer equipment and software 3 -5 years  The cost and accumulated depreciation of assets sold or retired are removed from their respective accounts, and any resulting net gain or loss is recognized in the accompanying consolidated statements of comprehensive loss. The carrying value of long-lived assets is reviewed on a regular basis for the existence of facts, both internally and externally, that may suggest impairment. Recoverability of assets to be held and used is measured by comparing the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the assets exceeds its estimated undiscounted future net cash flows, an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the assets.  Intangible Assets We capitalize outside legal costs and agency filing fees incurred in connection with securing the rights to our intellectual property. Patents, copyrights and other intangible assets are amortized using the straight-line method over their estimated period of benefit. We estimate the economic lives of our patents and copyrights to be fifteen to twenty years. Management evaluates the recoverability of intangible assets periodically and takes into account events or circumstances that may warrant revised estimates of useful lives or that may indicate impairment exists. As part of our ongoing patent maintenance program, we will, from time to time, abandon a particular patent if we determine fees to maintain the patent exceed its expected recoverability. The cost and accumulated amortization of abandoned intangible assets are removed from their respective accounts, and any resulting net loss is recognized in selling, general and administrative expenses in the accompanying consolidated statements of comprehensive loss.  Contingent Payment Obligations We have accounted for our secured and unsecured contingent payment obligations as long-term debt in accordance with Accounting Standards Codification (“ ASC ”) 470-10-25, “Sales of Future Revenues or Various other Measures of Income.” Our payment obligations are contingent upon the receipt of proceeds from patent enforcement and/or patent monetization actions. We have elected to measure our contingent payment obligations at their estimated fair values in accordance with ASC 825, “Financial Instruments” based on the variable and contingent nature of the repayment provisions. We have determined that the fair value of our secured and unsecured contingent payment obligations falls within Level 3 in the fair value hierarchy, which involves significant estimates, and assumptions including projected future patent-related proceeds and the risk-adjusted rate for discounting future cash flows (see Note 10). Actual results could differ from the estimates made. Changes in fair value, including the component related to imputed interest, are included in the accompanying consolidated statements of comprehensive loss under the heading “Change in fair value of contingent payment obligations.”  Leases We adopted ASC 842, “Leases” as of January 1, 2019 which requires the recognition of lease right-of-use (“ ROU ”) assets and lease liabilities on our consolidated balance sheets for finance and operating leases with initial lease terms of more than 12 months. We elected to use the effective date as the initial application date. ASC 842 provides a number of practical expedients in transition and we elected the package of practical expedients which permits us not to reassess under the new standard our prior conclusions about lease identification, lease classification and treatment of initial direct costs. The adoption of this new standard resulted in the recognition of operating lease ROU assets and operating lease liabilities of approximately $0.56 million and $0.60 million, respectively, primarily related to our facilities leases. Refer to Note 8 for additional disclosures related to our leases.  At inception of a lease, we determine if an arrangement contains a lease and whether that lease meets the classification criteria of a finance or operating lease. Some of our lease arrangements contain lease components (e.g. minimum rent payments) and non-lease components (e.g. services). For certain equipment leases, we account for lease and non-lease components separately based on a relative fair market value basis. For all other leases, we account for the lease and non-lease components (e.g. common area maintenance) on a combined basis.  For operating leases with terms greater than 12 months, we record the ROU asset and lease obligation at the present value of lease payments over the term using the implicit interest rate, when readily available, or our incremental borrowing rate for collateralized debt based on information available at the lease commencement date. Certain of our leases include rental escalation clauses, renewal options and/or termination options that are factored into our determination of lease payments when it is reasonably certain that the option will be exercised. We do not recognize ROU assets and lease liabilities for leases with terms at inception of twelve months or less.  Finance leases are included in property and equipment and other accrued expenses on the consolidated balance sheets. Finance leases are recorded as an asset and an obligation at an amount equal to the present value of the minimum lease payments during the lease term. Amortization expense and interest expense associated with finance leases are included in selling, general, and administrative expense and interest expense, respectively, on the consolidated statements of comprehensive loss.  Convertible Debt We have issued debt that is convertible, at the holder’s option, into shares of our common stock at fixed conversion prices. Certain of the convertible notes were issued with conversion prices that were below market value of our common stock on the closing date resulting in a beneficial conversion feature which we recorded to equity with a corresponding discount to the debt. The discount is amortized over the life of the notes as interest expense.  In August 2020, the Financial Accounting Standards Board issued ASU 2020-06 "Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity." This ASU simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. Consequently, more convertible debt instruments will be reported as a single liability instrument with no separate accounting for embedded conversion features. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception, which will permit more equity contracts to qualify for the exception. The ASU also simplifies the diluted earnings per share (EPS) calculation in certain areas. The ASU is effective for fiscal years beginning after December 15, 2021 for accelerated filers and for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, for smaller reporting companies. Early adoption is permitted for fiscal years beginning after December 15, 2020. The ASU provides for a modified retrospective method of adoption whereby the guidance is applied to transactions outstanding at the beginning of the fiscal year of adoption with the cumulative effect of the change being recorded as an adjustment to beginning retained earnings.  We plan to adopt ASU 2020-06, using the modified retrospective method, as of January 1, 2021. Adoption of ASU 2020-06 will result in an increase to our long-term debt of approximately $0.8 million, a decrease in additional paid-in-capital of approximately $1.1 million, and an adjustment to our beginning retained deficit of $0.3 million resulting from the elimination of the previously recognized beneficial conversion feature as a debt discount.  Revenue Recognition We account for revenue under ASC 606, “Revenue from Contracts with Customers” which implements a common revenue standard that clarifies the principles for recognizing revenue. This revenue recognition model provides a five-step analysis in determining when and how revenue is recognized.  We expect to derive future revenue from licensing of our intellectual property and settlements from patent infringement disputes. The timing of revenue recognition and the amount of revenue recognized depends upon a variety of factors, including the specific terms of each arrangement and the nature of our deliverables and obligations. In general, we recognize revenue when the performance obligations to our customers have been met. The consideration received from patent license and settlement agreements is allocated to the various elements of the arrangement to the extent the revenue recognition differs between the elements of the arrangement. Elements related to past and future royalties as well as elements related to settlement will be recorded as revenue in our consolidated statements of comprehensive loss when our performance obligations related to each element have been met.  For the year ended December 31, 2019, we recognized revenue from the sale of products. For product sales, the performance obligation is generally met at the time product is delivered to the customer. Estimated product returns are deducted from revenue and recorded as a liability. Revenue from the sale of our products includes shipping and handling charged to the customer. Product revenue is recorded net of sales tax collected from customers, discounts, and actual and estimated future returns.  Research and Development Expenses Research and development costs are expensed as incurred and include salaries and benefits for employees engaged in research and development activities, costs paid to third party contractors, prototype expenses, an allocated portion of facilities costs, maintenance costs for software development tools, and depreciation.  Accounting for Share-Based Compensation We have various share-based compensation programs which provide for equity awards including stock options, restricted stock units (“ RSUs ”) and restricted stock awards (“ RSAs ”). We calculate the fair value of employee share-based equity awards on the date of grant and recognize the calculated fair value as compensation expense over the requisite service periods of the related awards. We estimate the fair value of stock option awards using the Black-Scholes option valuation model. This valuation model requires the use of highly subjective assumptions and estimates including how long employees will retain their stock options before exercising them and the volatility of our common stock price over the expected life of the equity award. Such estimates, and the basis for our conclusions regarding such estimates, are outlined in detail in Note 14. Estimates of fair value are not intended to predict actual future events or the value ultimately realized by persons who receive equity awards. We account for forfeitures of share-based awards as they occur.  As of January 1, 2019, we adopted ASU 2018-07, "Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting." The amendments in this update simplify the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. At the time of adoption, we did not have any awards to nonemployees that would require reassessment and therefore the adoption of ASU 2018-07 did not impact our consolidated financial statements.  Income Taxes The provision for income taxes is based on loss before taxes as reported in the accompanying consolidated statements of comprehensive loss. Deferred tax assets and liabilities are recognized for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on differences between the financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established to reduce deferred tax assets when, based on available objective evidence, it is more likely than not that the benefit of such assets will not be realized. Our deferred tax assets exclude unrecognized tax benefits which do not meet a more-likely-than-not threshold for financial statement recognition for tax positions taken or expected to be taken in a tax return.  As of January 1, 2019, we adopted ASU 2018-02, “Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” The amendments in this update allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act. We have no stranded tax effects included in our other comprehensive loss and therefore the adoption of ASU 2018-02 did not impact our consolidated financial statements. Loss per Common Share Basic loss per common share is determined based on the weighted-average number of common shares outstanding during each year. Diluted loss per common share is the same as basic loss per common share as all potential common shares are excluded from the calculation, as their effect is anti-dilutive.  The number of shares underlying outstanding options, warrants, unvested RSUs, and convertible notes at December 31, 2020 and 2019 were as follows (in thousands):    2020 2019  Options outstanding 12,240 11,410  Warrants outstanding 12,850 12,150  Unvested RSUs 187 -  Shares underlying convertible notes 23,557 20,846  48,834 44,406   These potential shares were excluded from the computation of diluted loss per share as their effect would have been anti-dilutive.

Liquidity And Going Concern

Liquidity And Going Concern	12 Months Ended
	Dec. 31, 2020
Liquidity And Going Concern [Abstract]
Liquidity And Going Concern	2. LIQUIDITY AND GOING CONCERN  The accompanying consolidated financial statements as of and for the year ended December 31, 2020 were prepared assuming we will continue as a going concern, which contemplates that we will continue in operation and will be able to realize our assets and settle our liabilities and commitments in the normal course of business for a period of at least one year from the issuance date of these consolidated financial statements. These consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that could result should we be unable to continue as a going concern.  We have incurred significant losses from operations and negative cash flows in every year since inception and have utilized the proceeds from the sales of our equity and equity-linked securities and our contingent funding arrangements with third-parties to fund our operations, including our litigation costs. For the year ended December 31, 2020 , we incurred a net loss of approximately $ 19.6 million and negative cash flows from operations of approximately $ 4.8 million. At December 31, 2020 , we had a working capital deficit of approximately $3.8 million and an accumulated deficit of approximately $ 421.4 million. These circumstances raise substantial doubt about our ability to continue to operate as a going concern for a period of one year after the issuance date of these consolidated financial statements.  We had cash and cash equivalents of approximately $1.6 million at December 31, 2020. We received an additional $5.6 million in proceeds from debt and equity financings and warrant and option exercises in the first quarter of 2021, of which $3.0 million was used to settle outstanding accounts and notes payable for litigation costs (see Note 17). Our remaining capital resources will be used to fund our current obligations and ongoing operating costs; however these resources may not be sufficient to meet our liquidity needs for the next twelve months and we may be required to seek additional capital.  Our business plan is currently focused solely on our patent enforcement and technology licensing objectives. The timing and amount of proceeds from our patent enforcement actions are difficult to predict and there can be no assurance we will receive any proceeds from these enforcement actions.  Our ability to meet our liquidity needs for the twelve months after the issuance date of these financial statements is dependent upon one or more of (i) our ability to successfully negotiate licensing agreements and/or settlements relating to the use of our technologies by others in excess of our contingent payment obligations and (ii) our ability to raise additional capital from the sale of debt or equity securities or other financing arrangements. We anticipate that we will continue to invest in patent protection, licensing, and enforcement of our wireless technologies. We expect that revenue generated from patent enforcement actions, and technology licenses over the twelve months after the issuance date of these financial statements, if any, after deduction of payment obligations to our third-party litigation funder and legal counsel, may not be sufficient to cover our operating expenses. In the event we do not generate revenues, or other patent-asset proceeds, sufficient to cover our operational costs and contingent repayment obligation, we will be required to raise additional working capital through the sale of equity securities or other financing arrangements.  The long-term continuation of our business plan is dependent upon our ability to secure sufficient financing to support our business, and our ability to generate revenues and/or patent-related proceeds sufficient to offset expenses and meet our contingent payment obligation and other long-term debt repayment obligations. Failure to generate sufficient revenues, raise additional capital through debt or equity financings, and/or reduce operating costs could have a material adverse effect on our ability to meet our short and long-term liquidity needs and achieve our intended long-term business objectives. 

Inventories

Inventories	12 Months Ended
	Dec. 31, 2020
Inventories [Abstract]
Inventories	3. INVENTORIES  As of December 31, 2019, we had $0.55 million in finished goods inventories that were fully offset by an inventory reserve. All of our remaining inventories were disposed of in 2020.  The following table provides a reconciliation of our inventory reserves for the years ended December 31, 20 20 and 2019 , respectively (in thousands):     2020 2019  Inventory reserves at beginning of year $ 550 $ 982  Impairment charges - 6  Write down of impaired inventories - (438)  Disposal of inventory (550) -  Inventory reserves at end of year $ - $ 550  

Prepaid Expenses

Prepaid Expenses	12 Months Ended
	Dec. 31, 2020
Prepaid Expenses [Abstract]
Prepaid Expenses	4. PREPAID EXPENSES  Prepaid expenses consisted of the following at December 31, 20 20 and 2019 (in thousands):     2020 2019  Prepaid services $ 408 $ 221  Prepaid bonds for German statutory costs 142 188  Prepaid insurance 21 62  Prepaid licenses, software tools and support 11 17  Other prepaid expenses 17 17  $ 599 $ 505 

Property And Equipment, Net

Property And Equipment, Net	12 Months Ended
	Dec. 31, 2020
Property And Equipment, Net [Abstract]
Property And Equipment, Net	5. PROPERTY AND EQUIPMENT, NET  Property and equipment, at cost, consisted of the following at December 31, 2020 and 2019 (in thousands):     2020 2019  Equipment and software $ 218 $ 260  Leasehold improvements 19 33  Furniture and fixtures 30 43  267 336  Less accumulated depreciation (237) (266)  $ 30 $ 70   Depreciation expense related to property and equipment was approximately $0.03 million and $0.04 million in 2020 and 2019 , respectively.  In connection with the relocation of our corporate headquarters in July 2019 and October 2020 , we disposed of a number of assets that were no longer in use. For the years ended December 31, 2020 and 2019 , we recorded a loss on disposal of fixed assets of approximately $0.02 million and $0.01 million, respectively.  In connection with the closure of our Lake Mary facility in 2018, we reclassified equipment with a net book value of approximately $0.07 millio n to assets held for sale. We contracted with a third party for the consignment sale of these assets and completed sales for several assets in 2019 . For the year ended December 31, 2019 , we recognized a net loss of approximately $0.04 million on the sale and/or impairment of assets held for sale. The gains and losses on the sale or impairment of held for sale assets is included in selling, general and administrative expenses in the accompanying statements of comprehensive loss. 

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2020
Intangible Assets [Abstract]
Intangible Assets	6. INTANGIBLE ASSETS  Intangible assets consisted of the following at December 31, 2020 and 2019 (in thousands):     2020 2019   Patents and copyrights $ 14,948 $ 16,612  Less accumulated amortization (12,778) (13,734)  $ 2,170 $ 2,878   Amortization expense for each of the years ended December 31, 2020 and 2019 was approximately $0.4 million and $0.6 million, respectively. For the years ended December 31, 2020 and 2019 , we recorded losses on the disposal of intangible assets of approximately $0.3 million and $0.4 million, respectively.  Future estimated amortization expense for intangible assets that have remaining unamortized amounts as of December 31, 2020 is as follows (in thousands):     2021 $ 358  2022 321  2023 283  2024 270  2025 231  2026 and thereafter 707  Total $ 2,170  

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2020
Accrued Liabilities [Abstract]
Accrued Liabilities	7. ACCRUED LIABILITIES  Other accrued expenses consisted of the following at December 31, 2020 and 2019 (in thousands):    2020 2019  Advances $ 882 $ 500  Board compensation - 413  Other accrued expenses 54 168  $ 936 $ 1,081   Advances include amounts received from litigation counsel as advanced reimbursement of out-of-pocket expenses expected to be incurred by us and, at December 31, 2020, includes approximately $0.4 million received from investors for the purchase of equity securities in a January 2021 transaction (see Note 17) . Board compensation of $0.4 million at December 31, 2019 represents accrued and unpaid board fees from prior periods. In 2020, current and prior board members agreed to accept share-based compensation awards with an aggregate grant-date fair value of approximately $0.1 million as partial payment for the outstanding fees and waived the remaining unpaid fees .

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	8. LEASES  We lease our office and other facilities and certain office equipment under long-term, non-cancelable operating and finance leases. No new finance or operating leases commenced during the year s ended December 31, 2020 or 2019 . During the year ended December 31, 2020, we recognized an impairment loss of approximately $0.2 million on the ROU asset related to our Lake Mary office lease. We ceased use of this facility in 2018 as part of a restructuring of our operations. The value of our ROU asset included estimated future sublease income. Due to a number of factors, including the high vacancy rate of the building in which the space is located and the current COVID-19 environment, we determined securing a sublease for the space would be unlikely. The impairment loss recognized in 2020 represented the remaining carrying value of the asset and is included in selling, general, and administrative expenses in our consolidated statements of comprehensive loss.  Lease expense for operating leases is generally recognized on a straight-line basis over the lease term and is included in operating expenses on the consolidated statement of comprehensive loss. We recognized operating lease costs of $0.1 million and $0.4 million for the years ended December 31, 2020 and 2019, respectively.  Supplemental Cash Flow Information  The following table summarizes the supplemental cash flow information related to leases, including the ROU assets recognized upon adoption of the new lease standard (in thousands ):    Year Ended Year Ended  December 31, December 31,  2020 2019  Cash paid for amounts included in the measurement of lease liabilities:  Operating cash flows from operating leases $ 315 $ 314  Operating cash flows from finance leases - -  Financing cash flows from finance leases - 1   Non-cash activity  Right-of-use assets obtained in exchange for operating lease liabilities - 563  Assets obtained in exchange for finance lease liabilities - -   Other Information  The table below summarizes other supplemental information related to leases:    December 31, December 31,  2020 2019  Weighted-average remaining lease term (in years):  Operating leases 1.7 2.7  Finance leases - 0.3  Weighted average discount rate  Operating leases (1) 12.1% 12.0%  Finance leases - 8.7%  (1) Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019.  Undiscounted Cash Flows  The future maturities of lease liabilities consist of the following as of December 31, 20 20 (in thousands) :     Operating Leases Finance Leases  2021 $ 175 $ -  2022 166 -  2023 4 -  Thereafter - -  Total undiscounted lease payments 345 -  Less: imputed interest (40) -  Present value of lease liabilities 305 -  Less: current obligations under leases (146) -  Long-term lease obligations $ 159 $ -  

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2020
Long-Term Debt [Abstract]
Long-Term Debt	9. LONG-TERM DEBT  Notes Payable  Note Payable to a Related Party We have an unsecured promissory note payable of $0.8 million to Sterne, Kessler, Goldstein, & Fox, PLLC (“ SKGF ”), a related party (see Note 1 5 ), for outstanding unpaid fees for legal services . The note, as amended, accrues interest at 4% per annum and provides for monthly payments of principal and interest of $10,000 with a final balloon payment of approximately $0.68 million due at the maturity date of April 30, 2022 . We are currently in compliance with all the terms of the note , as amended. For the years ended December 31, 2020 and 2019 , we recognized interest expense of approximately $0.03 million and $0.04 million, respectively , related to this note .  Unsecured Notes Payable Unsecured notes payable at December 31, 2020 represents the current portion of our Paycheck Protection Program loan, as described more fully below. Unsecured notes payable at December 31, 2019 represents the outstanding principal balance of unsecured short-term promissory notes with accredited investors. The short-term promissory notes, as amended, accrued interest at a rate of 20% per annum. During the year ended December 31, 2020, we issued an aggregate of 1,740,426 shares of our common stock as an in-kind repayment of the $0.23 million in outstanding principal and $0.04 million of accrued interest on these short-term notes. For the years ended December 31, 2020 and 2019, we recognized interest expense of approximately $0.01 million and $0.03 million, respectively, related to these short-term notes.  Paycheck Protection Program Loan In May 2020, we received approximately $0.2 million in proceeds from an approved loan under the Paycheck Protection Program. Interest accrues on the outstanding principal balance at a rate of 1% , computed on a simple interest basis. The loan principal and accrued interest are expected to be eligible for forgiveness in accordance with the loan provisions. Payments of principal and interest are deferred until the date a decision on an application for forgiveness is made. If no application is submitted, we will be required to make monthly repayments of approximately $8,000 per month commencing May 1, 2021 and the loan will mature on May 3, 2022 , at which time any unpaid principal and accrued interest will be due and payable. We began the application process for loan forgiveness in March 2021. The estimated current and noncurrent portions of this loan are included in the captions “Unsecured notes payable” and “Other long-term liabilities” in the consolidated balance sheet as of December 31, 2020. Other long-term liabilities at December 31, 2019 represents an advance payment from a potential litigation funder. This liability was reclassified as an unsecured contingent payment obligation in 2020 (see “unsecured contingent payment obligation” below).  Secured Note Payable We have a note payable to Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (“ Mintz ”) for outstanding, unpaid attorney’s fees and costs associated with our patent enforcement program. The Mintz note is non-interest bearing, except in the event of a default, and is secured by certain of our U.S. and foreign patents. The note, at Mintz’s option, accelerates and becomes immediately due and payable in the case of standard events of default and/or in the event of a sale or other transfer of substantially all of our assets or a transfer of more than 50% of our capital stock in one or a series of transactions or through a merger or other similar transaction.  We were in default on the payment terms of the note at December 31, 2019, and accordingly, we accrued interest at the default rate of 12% per annum. During the year ended December 31, 2020, we repaid $1.2 million of outstanding principal and interest on the Mintz note, leaving an outstanding balance of accrued default interest, at December 31, 2020 of approximately $0.03 million. In March 2021, we settled our outstanding obligations with Mintz (see Note 17) and Mintz waived all past defaults on the note which has been paid in full.  At December 31, 2020 , the aggregate maturities of our notes payable are as follows (in thousands):     2021 $ 191  2022 832  Total $ 1,023   The estimated fair value of our notes payable at December 31, 2020 is approximately $0.9 million based on a risk-adjusted discount rate.  Convertible Notes  Our convertible notes represent five-year promissory notes that are convertible, at the holders’ option, into shares of our common stock at fixed conversion prices. Interest payments are made on a quarterly basis and are payable, at our option and subject to certain equity conditions, in either cash, shares of our common stock, or a combination thereof. To date, all interest payments on the convertible notes have been made in shares of our common stock. We have recognized the convertible notes as debt in our consolidated financial statements. The fixed conversion prices of certain of the notes were below the market value of our common stock on the closing date resulting in the recognition of a beneficial conversion feature that is recorded as a discount on the convertible notes with a corresponding increase to additional paid in capital.  Convertible notes payable at December 31, 2020 and 2019 , consist of the following (in thousands):     Fixed Effective  Conversion Interest December 31,  Description Rate Rate 1 Maturity Date 2020 2019  Convertible notes dated September 10, 2018 $0.40 23.4% September 7, 2023 $ 600 $ 700  Convertible notes dated September 19, 2018 $0.57 10.2% September 19, 2023 425 425  Convertible notes dated February/March 2019 $0.25 8.0% February 28, 2024 to March 13, 2024 1,300 1,300  Convertible notes dated June/July 2019 $0.10 8.0% June 7, 2024 to July 15, 2024 340 390  Convertible notes dated July 18, 2019 $0.08 46.1% July 18, 2024 700 700  Convertible notes dated September 13, 2019 $0.10 25.9% September 13, 2024 50 50  Convertible notes dated January 8, 2020 $0.13 20.3% January 8, 2025 450 -  Total principal balance 3,865 3,565  Less unamortized discount 847 832  $ 3,018 $ 2,733  1 The effective interest rate differs from the stated rate of interest on the notes as a result of beneficial conversion features recognized as discounts on the debt.  The notes bear interest at a stated rate of 8% per annum, except for the July 18, 2019 notes which bear interest at a stated rate of 7.5% per annum. We have the option to prepay the majority of the notes any time following the one-year anniversary of the issuance of the notes, subject to a premium on the outstanding principal prepayment amount of 25% prior to the two-year anniversary of the note issuance date, 20% prior to the three-year anniversary of the note issuance date, 15% prior to the four-year anniversary of the note issuance date, or 10% thereafter. The notes provide for events of default that include failure to pay principal or interest when due, breach of any of the representations, warranties, covenants or agreements made by us, events of liquidation or bankruptcy, and a change in control. In the event of default, the interest rate increases to 12% per annum and the outstanding principal balance of the notes plus all accrued interest due may be declared immediately payable by the holders of a majority of the then outstanding principal balance of the notes.  For the years ended December 31, 2020 and 2019 , we sold five -year convertible promissory notes with an aggregate face value of $0.45 million and $2.44 million , respectively and recorded debt discounts in an amount equal to the beneficial conversion features on these notes of approximately $0.17 million and $0.55 million , respectively . For the year ended December 31, 2020, convertible notes with a face value of $0.15 mi llion were converted by the holders into 750,000 shares of our common stock at a n average conversion price of $0.20 . F or the year ended December 31, 2019, convertible notes with a face value of $0.1 million were converted by the holders into 250,000 shares of our common stock at a fixed conversion price of $0.40 . At the holders’ option, subject to ownership limitations, the convertible notes outstanding at December 31, 2020 could be converted into an aggregate of approximately 23.6 million shares of our common stock based on the fixed conversion prices.  For the years ended December 31, 2020 and 2019 , we recognized interest expense of approximately $0.47 million and $0.32 million, respectively, including approximately $0.17 million and $0.12 million, respectively, related to amortization of the discount and $0.3 million and $0.2 million, respectively, related to the contractual interest which we elected to pay in shares of our common stock. For the years ended December 31, 2020 and 2019, we issued approximately 710,000 and 1,600,000 shares of our common stock, respectively, as interest-in-kind payments on our convertible notes. The unamortized discount on the convertible notes will be eliminated upon our adoption of ASU 2020-06 as of January 1, 2021 (see Note 1) .  All of the shares underlying our convertible notes, including shares reserved for future in-kind interest payments on the notes, have been registered for resale.  Secured Contingent Payment Obligation  The following table provides a reconciliation of our secured contingent payment obligation measured at estimated fair market value for the year s ended December 31, 2020 and 2019 , respectively (in thousands).      2020 2019  Secured contingent payment obligation, beginning of year $ 26,651 $ 25,557  Change in fair value 6,406 1,094  Secured contingent payment obligation, end of year $ 33,057 $ 26,651   Our secured contingent payment obligation represents the estimated fair value of our repayment obligation to Brickell Key Investments, LP (“ Brickell ”) under a February 2016 funding agreement, as amended from time to time (the “ CPIA ”). To date, we have received aggregate proceeds of $18 million in exchange for Brickell’s right to reimbursement and compensation from gross proceeds resulting from patent enforcement and other patent monetization actions. No proceeds were received from Brickell in 2019 or 2020 . To date, we have repaid an aggregate of $3.3 million under the CPIA from patent license and settlement proceeds.  Brickell is entitled to priority payment of 55% to 100% of proceeds received from all patent-related actions until such time that Brickell has been paid its minimum return. The minimum return is determined as a multiple of the funded amount that increases over time . The estimated minimum return due to Brickell was approximately $42 million and $39 million as of December 31, 2020 and 2019, respectively. In addition, Brickell is entitled to a pro rata portion of proceeds from specified legal actions to the extent aggregate proceeds from those actions exceed the minimum return .  Brickell holds a senior security interest in the majority of our assets until such time as the specified minimum return is paid, in which case, the security interest will be released except with respect to the patents and proceeds related to specific legal actions. The security interest is enforceable by Brickell in the event that we are in default under the agreement which would occur if (i) we fail, after notice, to pay proceeds to Brickell, (ii) we become insolvent or insolvency proceedings are commenced (and not subsequently discharged) with respect to us, (iii) our creditors commence actions against us (which are not subsequently discharged) that affect our material assets, (iv) we, without Brickell’s consent, incur indebtedness other than immaterial ordinary course indebtedness, or (v) there is an uncured non-compliance of our obligations or misrepresentations under the agreement. As of December 31, 20 20 , we are in compliance with our obligations under this agreement.  In addition, in the event of a change in control of the Company, Brickell has the right to be paid its return as defined under the CPIA based on the transaction price for the change in control event.  We have elected to measure our secured contingent payment obligation at its estimated fair value based on probability-weighted estimated cash outflows, discounted back to present value using a discount rate determined in accordance with accepted valuation methods (see Note 10). The secured contingent payment obligation is remeasured to fair value at each reporting period with changes recorded in the consolidated statements of comprehensive loss until the contingency is resolved.  Unsecured Contingent Payment Obligations  The following table provides a reconciliation of our unsecured contingent payment obligations, measured at estimated fair market value, for the years ended December 31, 2020 and 2019, respectively (in thousands):     2020 2019  Unsecured contingent payment obligations, beginning of period $ - $ -  Reclassification of other liabilities 1,003 -  Issuance of contingent payment rights 2,258 -  Change in fair value 1,961 -  Unsecured contingent payment obligations, end of period $ 5,222 $ -   Our unsecured contingent payment obligations represent amounts payable to others from future patent-related proceeds including (i) a termination fee due to a litigation funder (“ Termination Fee ”) and (ii) contingent payment rights (“ CPRs ”) issued to accredited investors primarily in connection with equity financings. We have elected to measure these unsecured contingent payment obligations at their estimated fair value based on probability-weighted estimated cash outflows, discounted back to present value using a discount rate determined in accordance with accepted valuation methods. The unsecured contingent payment obligations will be remeasured to fair value at each reporting period with changes recorded in the consolidated statements of comprehensive loss until the contingency is resolved (see Note 10).  The Termination Fee is a result of advances received under a letter agreement with a third-party funder of $0.4 million in 2019 and $0.6 million in 2020. Based on the terms of the letter agreement, if a final funding arrangement was not executed by March 31, 2020, we would be obligated to pay, from future patent-related proceeds, an aggregate termination payment equal to five times the advances received, or approximately $5.0 million. We did not consummate a funding agreement and accordingly the advances, which were initially recorded in other long-term liabilities, were reclassified to unsecured contingent payment obligations at March 31, 2020, when the Termination Fee obligation was incurred. As of December 31, 2020, the estimated fair value of unsecured contingent payment obligations related to the Termination Fee is $2.7 million.  The CPRs represent the estimated fair value of rights provided to accredited investors who purchased shares of our common stock and the fair value of a right issued to a third-party in connection with a service agreement during the year ended December 31, 2020 (see Note 13). During the year ended December 31, 2020, we received aggregate proceeds of $3.8 million from the sale of common stock with contingent payment rights, of which approximately $1.8 million was allocated to the CPRs. In addition, on May 1, 2020, we amended certain March 2020 equity purchase agreements with accredited investors for the purchase of $0.9 million in common stock to add CPRs. This amendment resulted in a charge to expense of $0.4 million for the initial estimated fair value of the CPRs. The terms of the CPRs provide that we will pay each investor an allocated portion of our net proceeds from patent-related actions, after taking into account fees and expenses payable to law firms representing us and amounts payable to Brickell. The investors’ allocated portion of net proceeds will be determined by multiplying the net proceeds recovered by us (up to $10 million) by the quotient of such investors’ subscription amount divided by $10 million, up to an amount equal to each investor’s subscription amount, or an aggregate of $4.7 million. As of December 31, 2020, the estimated fair value of our unsecured contingent payment obligations related to the CPRs is $2.5 million.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2020
Fair Value Measurements [Abstract]
Fair Value Measurements	10. FAIR VALUE MEASUREMENTS  ASC 820, “Fair Value Measurements” establishes a fair value hierarchy that prioritizes the inputs to valuation methods used to measure fair value. The three levels of the fair value hierarchy are as follows:  · Level 1: Quoted prices for identical assets or liabilities in active markets which we can access · Level 2: Observable inputs other than those described in Level 1 · Level 3: Unobservable inputs  The following table summarizes financial assets and financial liabilities carried at fair value and measured on a recurring basis as of December 31, 2020 and 2019 , segregated by classification within the fair value hierarchy (in thousands):    Fair Value Measurements  Total Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3)  December 31, 2020:  Liabilities:  Secured contingent payment obligation $ 33,057 $ - $ - $ 33,057  Unsecured contingent payment obligations 5,222 - - 5,222    December 31, 2019:  Liabilities:  Secured contingent payment obligation 26,651 - - 26,651  For the years ended December 31, 2020 and 2019 , respectively, we had no transfers of assets or liabilities between the levels of the hierarchy.  The fair values of our secured and unsecured contingent payment obligations were estimated using a probability-weighted income approach based on various cash flow scenarios as to the outcome of patent-related actions both in terms of timing and amount, discounted to present value using a risk-adjusted rate. We used a risk-adjusted discount rate of 14.15% at December 31, 2020, based on a risk-free rate of 0.15% as adjusted by 8% for credit risk and 6% for litigation inherent risk.  The following table provides quantitative information about the significant unobservable inputs used in the measurement of fair value for both the secured and unsecured contingent payment obligations at December 31, 2020, including the lowest and highest undiscounted payout scenarios as well as a weighted average payout scenario based on relative undiscounted fair value of each cash flow scenario.      Secured Contingent Payment Obligation Unsecured Contingent Payment Obligations  Unobservable Inputs Low Weighted Average High Low Weighted Average High   Estimated undiscounted cash outflows (in millions) $ 0.0 $ 46.1 $ 70.2 $ 0.0 $ 7.3 $ 9.7  Duration (in years) 1.0 2.5 3.5 1.0 2.5 3.5  Estimated probabilities 5% 23% 25% 25% 25% 25%   We evaluate the estimates and assumptions used in determining the fair value of our contingent payment obligations each reporting period and make any adjustments prospectively based on those evaluations. Changes in any of these Level 3 inputs could result in a significantly higher or lower fair value measurement

Income Taxes And Tax Status

Income Taxes And Tax Status	12 Months Ended
	Dec. 31, 2020
Income Taxes And Tax Status [Abstract]
Income Taxes And Tax Status	11. INCOME TAXES AND TAX STATUS  Our net losses before income taxes for the years ended December 31, 2020 and 2019 are from domestic operations as well as losses from our wholly-owned German subsidiary. We elected to treat our German subsidiary as a disregarded entity for purposes of income taxes and accordingly, the losses from our German subsidiary ha ve been included in our operating results.  No current or deferred tax provision or benefit was recorded in 2020 or 2019 as a result of current losses and fully deferred tax valuation allowances for all periods. We have recorded a valuation allowance to state our deferred tax assets at their estimated net realizable value due to the uncertainty related to realization of these assets through future taxable income.  A reconciliation between the provision for income taxes and the expected tax benefit using the federal statutory rate of 21% for each of the years ended December 31, 2020 and 2019 , respectively are as follows (in thousands):     2020 2019  Tax benefit at statutory rate $ (4,111) $ (1,985)  State tax benefit (842) (407)  Increase in valuation allowance 4,307 2,341  Other 646 51  $ - $ -   Our deferred tax assets and liabilities relate to the following sources and differences between financial accounting and the tax bases of our assets and liabilities at December 31, 2020 and 2019 (in thousands):     2020 2019  Gross deferred tax assets:  Net operating loss carry-forward $ 80,848 $ 83,865  Research and development credit carry-forward 6,603 7,608  Stock compensation 122 (28)  Patents and other 1,466 1,479  Contingent payment obligations 5,235 3,119  Inventories - 139  Fixed assets 54 3  Accrued liabilities 64 200  Lease liabilities 77 142  Other - 3  94,469 96,530  Less valuation allowance (94,245) (96,320)  224 210  Gross deferred tax liabilities:  Convertible debt (224) (210)  (224) (210)  Net deferred tax asset $ - $ -   Approximately $0.2 million, net of tax effect, of unrecognized tax benefit related to the beneficial conversion feature of convertible debt would be recorded as an adjustment to contributed capital rather than a decrease in earnings, if recognized.  At December 31, 2020 , we had cumulative net operating loss (“ NOL ”) carry-forwards for income tax purposes of $323.2 million, of which $294.1 million is subject to expiration in varying amounts from 2021 to 2037 . At December 31, 2020 , we also had research and development tax credit carryforwards of $6.6 million, which expire in varying amounts from 2021 through 2038 .  Our ability to benefit from the tax credit carry-forwards could be limited under certain provisions of the Internal Revenue Code if there are ownership changes of more than 50%, as defined by Section 382 of the Internal Revenue Code of 1986 (“ Section 382 ”). Under Section 382, an ownership change may limit the amount of NOL, capital loss and R&D credit carry-forwards that can be used annually to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain shareholders or public groups in the stock of a corporation by more than 50 percentage points over a three-year period. We conduct a study annually of our ownership changes. Based on the results of our studies, we have determined that we do not have any ownership changes on or prior to December 31, 2020 which would result in limitations of our NOL, capital loss or R&D credit carry-forwards under Section 382.  Uncertain Tax Positions We file income tax returns in the U.S. federal jurisdiction , various state jurisdictions , and Germany . We have identified our Federal and Florida tax returns as our only major jurisdictions, as defined. The periods subject to examination for those returns are the 2001 through 2020 tax years. The following table provides a reconciliation of our unrecognized tax benefits due to uncertain tax positions for the years ended December 31, 2020 and 2019 , respectively (in thousands):     2020 2019  Unrecognized tax benefits – beginning of year $ 927 $ 927  Unrecognized tax benefits – end of year $ 927 $ 927   Future changes in the unrecognized tax benefit will have no impact on the effective tax rate so long as we maintain a full valuation allowance.  Our policy is that we recognize interest and penalties accrued on any unrecognized tax benefits as a component of our income tax expense. We do not have any accrued interest or penalties associated with any unrecognized tax benefits. For the years ended December 31, 2020 and 2019 , we did not incur any income tax-related interest income, expense or penalties.

Commitments And Contingencies

Commitments And Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments And Contingencies [Abstract]
Commitments And Contingencies	12. COMMITMENTS AND CONTINGENCIES  Legal Proceedings From time to time, we are subject to legal proceedings and claims which arise in the ordinary course of our business. These proceedings include patent enforcement actions initiated by us against others for the infringement of our technologies, as well as proceedings brought by others against us at the Patent Trial and Appeal Board of the U.S. Patent and Trademark Office (“ PTAB ”) and in the Federal Patent Court in Germany in an attempt to invalidate certain of our patent claims.  We ha d several patent enforcement actions in Germany in which we did not prevail. Germany has a “loser pay” system whereby the non-prevailing party is responsible for statutory attorney fees and costs. All of our German actions were concluded in 2019. We have recorded an estimated loss for statutory attorney fees and costs in current liabilities under the heading “statutor y court costs” in the consolidated balance sheets. As of December 31, 2020 and 2019 , we have accrued an aggregate of $0.25 million and $0.37 million, respectivel y, for our concluded cases in Germany . We also have a bond posted in Germany that upon release will satisfy $0.14 million of these accrued costs. The bond is recorded in prepaid expenses (see Note 4).  ParkerVision v. Qualcomm (Middle District of Florida) We have a patent infringement complaint pending in the Middle District of Florida against Qualcomm and Qualcomm Atheros, Inc. (collectively “ Qualcomm ”) seeking approximately $1.3 billion in damages for infringement of four of our patents (the “ Qualcomm Action ”). HTC Corporation and HTC America, Inc. (collectively “ HTC ”) were also defendants in this case but we voluntarily dismissed our claims against HTC and HTC dismissed their related counter-claims against us in October 2020. Qualcomm has pending counterclaims against us for non-infringement and invalidity for all patents in the case. The case was filed in May 2014 and stayed in February 2016 pending decisions in other cases, including the appeal of a PTAB proceeding with regard to U.S. patent 6,091,940 (“ the ‘940 Patent ”) asserted in this case. In March 2017, the PTAB ruled in our favor on three of the six petitions (the method claims), ruled in Qualcomm’s favor on two of the six petitions (the apparatus claims) and issued a split decision on the claims covered in the sixth petition. In September 2018, the Federal Circuit upheld the PTAB’s decision with regard to the ‘940 Patent and, in January 2019, the court lifted the stay in this case. In July 2019, the court issued an order that granted our proposed selection of patent claims from four asserted patents, including the ‘940 Patent, and denied Qualcomm’s request to limit the claims and patents. The court also agreed that we may elect to pursue accused products that were at issue at the time the case was stayed, as well as new products that were released by Qualcomm during the pendency of the stay. In September 2019, Qualcomm filed a motion for partial summary judgement in an attempt to exclude certain patents from the case, including the ‘940 Patent. The court denied this motion in January 2020. In April 2020, the court issued its claim construction order in which the court adopted our proposed construction for seven of the ten disputed terms and adopted slightly modified versions of our proposed construction for the remaining terms. Due to the impact of COVID-19, a number of the scheduled deadlines in this case were moved including the trial commencement date which was rescheduled from December 2020 to May 2021. We are seeking $1.3 billion in royalties owed to us by Qualcomm for its unauthorized use of our technology, based on a report submitted by our damages expert in this case in October 2020. Such amount excludes additional amounts requested by us for interest and enhanced damages for willful infringement. Ultimately, the amount of damages, if any, will be determined by the court. Discovery was expected to close in December 2020; however, the court allowed us to designate a substitute expert due to medical issues with one of our experts in the case. Accordingly, the close of discovery was delayed until January 2021. As a result of these delays, the court rescheduled the trial commencement date from May 3, 2021 to July 6, 2021. Fact and expert discovery in this case are closed, expert reports have been submitted, and summary judgement and Daubert briefings have been completed by the parties. In March 2021, the court granted Qualcomm’s motion to strike certain of our 2020 infringement contentions. A number of outstanding motions are pending decisions by the court. On March 26, 2021, the court further delayed the trial date citing backlog due to the pandemic, among other factors. A new trial date has not yet been set although the court indicated the case was unlikely to be tried before November or December 2021. We are represented in this case on a full contingency fee basis.  ParkerVision v. Apple and Qualcomm (Middle District of Florida) In December 2015, we filed a patent infringement complaint in the Middle District of Florida against Apple, LG, Samsung and Qualcomm alleging infringement of four of our patents. In February 2016, the district court proceedings were stayed pending resolution of a corresponding case filed at the International Trade Commission (“ ITC ”). In July 2016, we entered into a patent license and settlement agreement with Samsung and, as a result, Samsung was dismissed from the district court action. In March 2017, we filed a motion to terminate the ITC proceedings and a corresponding motion to lift the stay in the district court case. This motion was granted in May 2017. In July 2017, we filed a motion to dismiss LG from the district court case and re-filed our claims against LG in the District of New Jersey (see ParkerVision v. LG below). Also in July 2017, Qualcomm filed a motion to change venue to the Southern District of California, and Apple filed a motion to dismiss for improper venue. In March 2018, the district court ruled against the Qualcomm and Apple motions. The parties also filed a joint motion in March 2018 to eliminate three of the four patents in the case in order to expedite proceedings leaving our U.S. patent 9,118,528 as the only remaining patent in this case. A claim construction hearing was held on August 31, 2018. In July 2019, the court issued its claim construction order in which the court adopted our proposed claim construction for two of the six terms and the “plain and ordinary meaning” on the remaining terms. In addition, the court denied a motion filed by Apple for summary judgment. Fact discovery has closed in this case and a jury trial was scheduled to begin in August 2020. In March 2020, as a result of the impact of COVID-19, the parties filed a motion requesting an extension of certain deadlines in the case. In April 2020, the court stayed this proceeding pending the outcome of the Qualcomm Action. We are represented in this case on a limited success fee basis.  ParkerVision v. LG (District of New Jersey) In July 2017, we filed a patent infringement complaint in the D istrict of New Jersey against LG for the alleged infringement of the same patents previously asserted against LG in the Middle D istrict of Florida (see ParkerVision v. Apple and Qualcomm above). We elected to dismiss the case in the M iddle D istrict of Florida and re-file in New Jersey as a result of a Supreme Court ruling regarding proper venue. In March 2018, the court stayed this case pending a final decision in ParkerVision v. Apple and Qualcomm in the Middle District of Florida. As part of this stay, LG has agreed to be bound by the final claim construction decision in that case. We are represented in this case on a limited success fee basis.  ParkerVision v. Intel (Western District of Texas) In February 2020, we filed a patent infringement complaint in the Western District of Texas against Intel alleging infringement of eight of our patents. The complaint was amended in May 2020 to add two additional patents. In June 2020, we requested that one of the patents be dropped from this case and filed a second case in the Western District of Texas that included this dismissed patent (see ParkerVision v. Intel II below). Intel’s response to our complaint was filed in June 2020 denying infringement and claiming invalidity of the patents. Intel also filed a motion to transfer venue which the court denied in January 2021. The court issued its claim construction ruling in January 2021 in which the majority of the claims were decided in our favor. The case is scheduled for trial beginning February 7, 2022. We are represented in this case on a full contingency fee basis.  Intel v. ParkerVision (PTAB) Intel filed petitions for Inter Partes Review (IPR) against U.S. patent 7,539,474 (“ the ‘474 Patent ”), U.S. patent 7,110,444 (“ the ‘444 Patent ”) and U.S. patent 8,190,108 (“ the ‘108 patent ”), all of which are patents asserted in ParkerVision v. Intel . In January 2021, the PTAB issued its decision to institute IPR proceeding for the ‘444 Patent and the ‘474 Patent. Our response to the instituted IPRs is due in April 2021. The PTAB has not yet issued a decision for the ‘108 Patent.  ParkerVision v. Intel II (Western District of Texas) In June 2020, to reduce the number of claims in ParkerVision v. Intel , we filed a second patent infringement complaint in the Western District of Texas against Intel that included a single patent that we voluntarily dismissed from the original case. In July 2020, we amended our complaint adding two more patents to the case. The claim construction hearing is expected to be scheduled after May 2021 and the case is currently scheduled for trial beginning March 17, 2022. We are represented in this case on a full contingency fee basis.  ParkerVision filed a number of additional patent cases in the Western District of Texas including cases against (i) TCL Industries Holdings Co., Ltd, a Chinese company, TCL Electronics Holdings Ltd., Shenzhen TCL New Technology Co., Ltd, TCL King Electrical Appliances (Huizhou) Co., Ltd., TCL Moka Int’l Ltd. and TCL Moka Manufacturing S.A. DE C.V. (collectively “ TCL ”), (ii) Hisense Co., Ltd. and Hisense Visual Technology Co., Ltd (collectively “ Hisense ”), a Chinese company, (iii) Buffalo Inc., a Japanese company (“ Buffalo ”)and (iv) Zyxel Communications Corporation, a Chinese multinational electronics company headquartered in Taiwan, (“ Zyxel ”). Each case alleges infringement of the same ten patents by products that incorporate modules containing certain Wi-Fi chips manufactured by Realtek and/or MediaTek. Each of the defendants have filed responses denying infringement and claiming invalidity of the patents, among other defenses. We are represented in each of these cases on a full contingency fee basis. 

Stock Authorization And Issuanc

Stock Authorization And Issuance	12 Months Ended
	Dec. 31, 2020
Stock Authorization And Issuance [Abstract]
Stock Authorization And Issuance	13. STOCK AUTHORIZATION AND ISSUANCE Preferred Stock We have 15 million shares of preferred stock authorized for issuance at the direction of our board of directors (the “ Board ”). On November 17, 2005, our Board designated 0.1 million shares of authorized preferred stock as the Series E Preferred Stock in conjunction with its adoption of a Shareholder Protection Rights Agreement. As of December 31, 2020 , we had no outstanding preferred stock.  Common Stock We have 140 million shares of common stock authorized for issuance as of December 31, 2020 . Our shareholders approved amendments to our articles of incorporation in November 2019 increas ing the number of our authorized shares of common stock from 75 million to 110 million shares and in July 2020 increasing the number of our authorized shares of common stock from 110 million to 140 million shares.  As of December 31, 2020 , we have 25.3 million s hares reserved for issuance under outstanding warrants , options, and RSUs and 23.6 million shares reserved for issuance upon conversion of our outstanding convertible notes. In addition, we have 0.2 million shares reserved for future issuance under equity compensation plans and 7.5 million shares reserved for the payment of interest in-kind on our convertible notes.  Stock and Warrant Issuances – Equity Based Financings During the year ended December 31, 2019, we did not issue any stock or warrants in financing transactions. The following table presents a summary of completed equity-based financing transactions for the year ended December 31, 20 20 (in thousands, except for per share amounts):    Date Transaction # of Common Shares/ Units Sold Average Price per Share/Unit # of Warrants Issued (in 000’s) Average Exercise Price per Warrant Net Proceeds (1)  January 2020 Private placement of common stock 1,335 $0.13 - - $ 177  February 2020 Warrant amendment - - 5,000 $0.74 $ -  March 2020 Private placement of common stock, amended to add CPR 2,571 $0.35 - - $ 900  April 2020 to December 2020 Private placement of common stock with CPRs 10,858 $0.35 - - $ 3,724  (1) After deduction of applicable offering costs.  Private Placements In January 2020, we entered into securities purchase agreements with accredited investors for an aggregate of 1,169,232 shares of our common stock at a price of $0.13 per share and 166,667 shares of our common stock at $0.15 per share for aggregate proceeds of approximately $0.2 million.  In March 2020, we entered into securities purchase agreements with accredited investors for an aggregate of 2,571,432 shares of our common stock at a price of $0.35 per share for aggregate proceeds of $0.9 million. The securities purchase agreements for the March 2020 transactions were amended on May 1, 2020, in order to add a contingent payment right whereby we will pay each investor an allocated portion of our share of proceeds from patent-related actions, after taking into account fees and expenses payable to law firms representing the Company and amounts payable to Brickell, up to an amount equal to the investors’ aggregate subscription amount, or $0.9 million (see “unsecured contingent payment obligations” in Note 9). The shares were registered for resale on a registration statement that was declared effective on April 28, 2020 (File No. 333-237762).  From April to December 2020, we entered into securities purchase agreements with accredited investors for an aggregate of 10,857,876 shares of our common stock at a price of $0.35 per share for aggregate proceeds of $3.8 million. The securities purchase agreements include contingent payment rights. Approximately $1.8 million of the proceeds were allocated to unsecured contingent payment obligations based on the initial fair value estimate of the CPRs (see Note 9). The shares sold from April to August, totaling 5,871,584 shares, were registered for resale on a registration statement that was declared effective on September 2, 2020 (File No. 333-248242).  For the s hares sold subsequent to August 2020 , w e entered into registration rights agreements with the investors pursuant to which we will register the shares. We have committed to file the registration statement by April 15, 2021 and to cause the registration statement to become effective by June 30, 2021 . The registration rights agreements provide for liquidated damages upon the occurrence of certain events including failure by us to file the registration statement or cause it to become effective by the deadlines set forth above. The amount of the liquidated damages is 1.0% of the aggregate subscription upon the occurrence of the event, and monthly thereafter, up to a maximum of 6% , or approximately $0.1 million. Warrant Amendment On February 28, 2020, we entered into a warrant amendment agreement (the “ Warrant Amendment Agreement ”) with Aspire Capital Fund, LLC (“ Aspire ”), with respect to warrants issued in July and September 2018 (the “ 2018 Warrants ”) that are exercisable, collectively, into 5,000,000 shares of our common stock. The Warrant Amendment Agreement provided for a reduction in the exercise price for the 2018 Warrants from $0.74 to $0.35 per share and the issuance of a new warrant for the purchase of 5,000,000 shares of our common stock at an exercise price of $0.74 per share (“ New Aspire Warrant ”). The New Aspire Warrant expires February 28, 2025 and is subject to adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock and upon any distributions of assets to our stockholders. The New Aspire Warrant contains provisions that prohibit exercise if the holder, together with its affiliates, would beneficially own in excess of 9.99% of the number of shares of common stock outstanding immediately after giving effect to such exercise. The holder of the New Aspire Warrant may increase (up to 19.99% ) or decrease this percentage by providing at least 61 days’ prior notice to the Company. In the event of certain corporate transactions, the holder of the New Aspire Warrant will be entitled to receive, upon exercise of such New Aspire Warrant, the kind and amount of securities, cash or other property that the holder would have received had they exercised the New Aspire Warrant immediately prior to such transaction. The New Aspire Warrant does not contain voting rights or any of the other rights or privileges as a holder of our common stock.  We recognized $1.78 million of non-cash warrant expense in connection with the Warrant Amendment Agreement based on the difference between the Black-Scholes value of the warrants immediately before and after the amendment. The Warrant Amendment Agreement added a call provision to the 2018 Warrants whereby we may, after December 31, 2020, call for cancellation of all or any portion of the 2018 Warrants for which an exercise notice has not yet been received, in exchange for consideration equal to $0.001 per warrant share and subject to certain conditions. All other terms of the 2018 Warrants remained unchanged, including the original expiration dates of July and September 2023. The shares underlying the New Aspire Warrant were registered for resale on a registration statement that was declared effective on April 28, 2020 (File No. 333-237762). The shares underlying the 2018 Warrants are currently registered for resale pursuant to a registration statement on Form S-1 (File No. 333-226738).  In connection with the Warrant Amendment Agreement, Aspire exercised 1,430,000 shares of the 2018 Warrants for aggregate proceeds to us of $0.5 million. An additional 3,070,000 shares of the 2018 Warrants were exercised during the year ended December 31, 2020 for aggregate additional proceeds to us of approximately $1.1 million. We did not exercise the call provision and the Aspire exercised the remaining 2018 Warrants in January 2021 (see Note 17).  Stock and Warrant Issuances – Payment for Services On February 10, 2020, we entered into a business consulting and retention agreement with Chelsea Investor Relations (“ Chelsea ”) to provide business advisory services to us. As consideration for services to be provided under the 24 -month term of the consulting agreement, we issued 500,000 shares of unregistered common stock in exchange for a nonrefundable retainer for services valued at approximately $0.15 million. The value of the stock issued is being recognized as consulting expense over the term of the agreement. The shares were registered for resale on a registration statement that was declared effective on April 28, 2020 (File No. 333-237762). The agreement was amended in January 2021 (see Note 17).  On March 16, 2020, we entered into an agreement with Tailwinds Research Group LLC (“ Tailwinds ”) to provide digital marketing services to us. As consideration for services to be provided under the twelve-month term of the agreement, we issued warrants for the purchase up to 200,000 shares of our common stock with an exercise price of $1.00 per share in exchange for a nonrefundable retainer for services, valued using the Black-Scholes method, at approximately $0.06 million. The value of the warrants is being recognized as expense over the term of the agreement. The Tailwinds warrants are exercisable immediately after issuance, expire March 16, 2023, and are subject to adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock. The shares underlying the warrant were registered for resale on a registration statement that was declared effective on April 28, 2020 (File No. 333-237762).  On June 8, 2020, we entered into an agreement with a third party to provide media advisory services. As consideration for services provided under the term of the agreement, which extended through December 31, 2020, we issued 30,000 shares of unregistered common stock for a nonrefundable retainer for services valued at approximately $0.01 million. The value of the stock issued was recognized as a consulting expense over the term of the agreement. We are not obligated to register the shares for resale.  On October 30, 2020, we entered into a consulting services agreement with a third-party to provide shareholder relations services. As consideration for services provided under the twelve-month term of the agreement, we issued 70,000 shares of unregistered common stock for a non-refundable retainer for services valued at approximately $0.02 million. The agreement included a CPR to receive up to $0.02 million from patent-related proceeds. The CPR was recorded as debt at its estimated fair value of approximately $0.1 million (see “unsecured contingent payment obligations” in Note 9).  During the year ended December 31, 2020, we issued an aggregate of 100,000 shares of our unregistered common stock, valued at approximately $0.05 million, as compensation for shareholder awareness services provided by a third party. The agreement provides for future issuances of 50,000 shares for up to two successive three-month periods over the term of the agreement, unless the services are terminated in accordance with the agreement. In January 2021, we issued 50,000 shares valued at approximately $0.03 million as the third quarterly payment under this agreement.  Common Stock Warrants As of December 31, 2020 and 2019 , we had outstanding warrants for the purchase of up to 12.9 million shares and 12.2 million shares of our common stock, respectively. The estimated grant date fair value of these warrants of $1.7 million and $1.3 million at December 31, 2020 and 2019 , respectively, is included in shareholders’ deficit in our consolidated balance sheets. As of December 31, 2020 , our outstanding warrants have an average exercise price of $0.45 per share and a weighted average remaining life of approximately three years.  Shareholder Protection Rights Agreement On November 20, 2020, we adopted a second amend ment to our Shareholder Protection Rights Agreement (“ Rights Agreement ”) dated November 21, 2005 , as amended . The amendment extends the expiration date of the Rights Agreement from November 2 0 , 20 20 to November 20, 202 3 and decreases the exercise price of the rights from $14.50 to $8.54 .  The Rights Agreement provided for the issuance, on November 29, 2005, as a dividend, rights to acquire fractional shares of Series E Preferred Stock. We did not assign any value to the dividend, as the value of these rights is not believed to be objectively determinable. The principal objective of the Rights Agreement is to cause someone interested in acquiring us to negotiate with our Board rather than launch an unsolicited or hostile bid. The Rights Agreement subjects a potential acquirer to substantial voting and economic dilution. Each share of common stock issued by ParkerVision will include an attached right.  The rights initially are not exercisable and trade with the common stock of ParkerVision. In the future, the rights may become exchangeable for shares of Series E Preferred Stock with various provisions that may discourage a takeover bid. Additionally, the rights have what are known as “flip-in” and “flip-over” provisions that could make any acquisition of us more costly to the potential acquirer. The rights may separate from the common stock following the acquisition of 15% or more of the outstanding shares of common stock by an acquiring person. Upon separation, the holder of the rights may exercise their right at an exercise price of $8.54 per right (the “ Exercise Price ”), subject to adjustment and payable in cash. Upon payment of the Exercise Price, the holder of the right will receive from us that number of shares of common stock having an aggregate market price equal to twice the Exercise Price, as adjusted. The Rights Agreement also has a flip over provision allowing the holder to purchase that number of shares of common/voting equity of a successor entity, if we are not the surviving corporation in a business combination, at an aggregate market price equal to twice the Exercise Price. We have the right to substitute for any of our shares of common stock that we are obligated to issue, shares of Series E Preferred Stock at a ratio of one ten-thousandth of a share of Series E Preferred Stock for each share of common stock. The Series E Preferred Stock, if and when issued, will have quarterly cumulative dividend rights payable when and as declared by the Board, liquidation, dissolution and winding up preferences, voting rights and will rank junior to other securities of ParkerVision unless otherwise determined by the Board. The rights may be redeemed upon approval of the Board at a redemption price of $0.01 . A s of December 31, 2020, there are no Series E preferred shares outstanding.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-Based Compensation [Abstract]
Share-Based Compensation	14. SHARE-BASED COMPENSATION  The following table presents share-based compensation expense included in our consolidated statements of comprehensive loss for the years ended December 31, 2020 and 2019 , respectively (in thousands):     2020 2019  Research and development expense $ - $ 5  Selling, general, and administrative expense 1,244 584  Total share-based compensation expense $ 1,244 $ 589   We did not capitalize any expense related to share-based payments. As of December 31, 2020 , there was $0.36 million of total unrecognized compensation cost related to all non-vested share-based compensation awards. That cost is expected to be recognized over a weighted-average period of approximately 0.5 years.  Stock Incentive Plans 2019 Long-Term Incentive Equity Plan We adopted a long-term incentive equity plan in August 2019 that provides for the grant of stock-based awards to employees, officers, directors and consultants, not to exceed 12.0 million shares of common stock (the “ 2019 Plan ”). The 2019 Plan provides for benefits in the form of nonqualified stock options, stock appreciation rights, restricted stock awards, and other stock based awards. Forfeited and expired options under the 201 9 Plan become available for reissuance. The plan provides that no n-employee directors may not be granted awards that exceed the lesser of 1.0 million shares or $175,000 in value, calculated based on grant-date fair value . At December 31, 2020 , 155,000 shares of common stock were available for future grants under the 2019 Plan. The 2019 Plan was amended in January 2021 (see Note 17).  2011 Long-Term Incentive Equity Plan We adopted a long-term incentive equity plan in September 2011 that, as amended in 2014, 2016 and 2017, provides for the grant of stock-based awards to employees, officers, directors and consultants, not to exceed 3.0 million shares of common stock (the “ 2011 Plan ”). The 2011 Plan provides for benefits in the form of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, and other stock based awards. Forfeited and expired options under the 2011 Plan become available for reissuance. The plan provides that no participant may be granted awards in excess of 150,000 shares in any calendar year. At December 31, 2020 , 25,627 shares of common stock were available for future grants under the 2011 Plan.  2008 Equity Incentive Plan We adopted an equity incentive plan in August 2008 (the “ 2008 Plan ”). The 2008 Plan provides for the grant of stock-based awards to employees (excluding named executives), directors and consultants, not to exceed 50,000 shares of common stock. The 2008 Plan provides for benefits in the form of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, and other stock based awards. Forfeited and expired options under the 2008 Plan become available for reissuance. The plan provides that no participant may be granted awards in excess of 5,000 shares in any calendar year. At December 31, 2020 , 20,473 shares of common stock were available for future grants under the 2008 Plan.  Restricted Stock Awards RSAs are issued as executive and employee incentive compensation and as payment for services to others. The value of the award is based on the closing price of our common stock on the date of grant. RSAs are generally immediately vested.  Restricted Stock Units RSUs are issued as incentive compensation to executives, employees, and non-employee directors. Each RSU represents a right to one share of our common stock, upon vesting. The RSUs are not entitled to voting rights or dividends, if any, until vested. RSUs generally vest over a one to three year period for employee awards and a one year period for non-employee director awards. The fair value of RSUs is generally based on the closing price of our common stock on the date of grant and is amortized to share-based compensation expense over the estimated life of the award, generally the vesting period .  RSAs and RSUs  The following table presents a summary of RSA and RSU activity under the 2000, 2008, 2011, and 2019 Plans (collectively, the “ Stock Plans ”) as of December 31, 2020 (shares in thousands):      Non-vested Shares  Shares Weighted-Average Grant Date Fair Value  Non-vested at beginning of year - $ -  Granted 1,016 0.31  Vested (829) 0.31  Forfeited - -  Non-vested at end of year 187 $ 0.33   The total fair value of RSAs and RSUs vested under the Stock Plans for the year ended December 31, 2020 was approximately $0.3 million.  Stock Options Stock options are issued as incentive compensation to executives, employees and non-employee directors. Stock options are generally granted with exercise prices at or above fair market value of the underlying shares at the date of grant. The fair value of options granted is estimated using the Black-Scholes option pricing model. Generally, fair value is determined as of the grant date. Options for employees, including executives and non-employee directors, are generally granted under the Stock Plans.  The following table presents a summary of option activity under the Stock Plans for the year ended December 31, 2020 (shares in thousands):    Shares Weighted- Average Exercise Price Weighted-Average Remaining Contractual Term Aggregate Intrinsic Value ($)  Outstanding at beginning of year 11,410 $ 0.33  Granted 843 0.31  Exercised - -  Forfeited/Expired (13) 38.86  Outstanding at end of year 12,240 0.28 5.5 years $ 3,401  Vested at end of year 9,490 $ 0.31 5.5 years $ 2,578   The weighted average per share fair value of options granted during the years ended December 31, 2020 and 2019 was $0.27 and $0.14 , respectively. The total fair value of option shares vested was $0.9 million and $0.5 million for the year ended December 31, 2020 and 2019, respectively .  The fair value of option grants under the Stock Plans for the years ended December 31, 2020 and 2019 , respectively, was estimated using the Black-Scholes option-pricing model with the following assumptions:     Year ended December 31,  2020 2019  Expected option term 1 5 years 5 years  Expected volatility factor 2 127.4% to 135.3% 119.1%  Risk-free interest rate 3 0.33% to 1.63% 1.6%  Expected annual dividend yield 0% 0%  1 The expected term was generally determined based on historical activity for grants with similar terms and for similar groups of employees and represents the period of time that options are expected to be outstanding. For employee options, groups of employees with similar historical exercise behavior are considered separately for valuation purposes. 2 The stock volatility for each grant is measured using the weighted average of historical daily price changes of our common stock over the most recent period equal to the expected option life of the grant. 3 The risk-free interest rate for periods equal to the expected term of the share option is based on the U.S. Treasury yield curve in effect at the measurement date.  Options by Price Range The options outstanding at December 31, 2020 under all plans have exercise price ranges, weighted average contractual lives, and weighted average exercise prices as follows (weighted average lives in years and shares in thousands):     Options Outstanding Options Vested  Range of Exercise Prices Number Outstanding at December 31, 2020 Wtd. Avg. Exercise Price Wtd. Avg. Remaining Contractual Life Number Exercisable at December 31, 2020 Wtd. Avg. Exercise Price Wtd. Avg. Remaining Contractual Life  $0.171 - $0.33 11,318 $ 0.18 5.6 8,624 $ 0.18 5.6  $0.50 - $0.60 513 0.59 5.0 457 0.60 4.8  $1.98 - $2.13 381 2.02 3.4 381 2.02 3.4  $13.80 28 13.80 0.5 28 13.80 0.5  12,240 $ 0.28 5.5 9,490 $ 0.31 5.5   Upon exercise of options under all plans, we issue new shares of our common stock. For shares issued upon exercise of equity awards granted under the Stock Plans, the shares of common stock are registered. For shares issued upon exercise of non-plan awards, the shares are not registered unless they have been subsequently registered by us on a registration statement. We had no option exercises for the years ended December 31, 2020 or 2019 .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	1 5 . RELATED PARTY TRANSACTIONS  We paid approximately $0.01 million and $0.02 million in 2020 and 2019 , respectively, for patent-related legal services to SKGF, of which Robert Sterne, one of our directors since September 2006, is a partner. In addition, we paid approximately $0.1 million in 2020 for principal and interest on the SKGF Note (refer to “Note Payable to a Related Party” included Note 9) . No payments were made in 2019 on the SKGF Note. The SKGF Note has an outstanding balance, including accrued interest, of approximately $0.8 million at December 31, 2020 .  In January 2020, we issued 500,000 in unregistered shares of our common stock as an in-kind payment of approximately $0.08 million in outstanding amounts payable to Stacie Wilf, sister to Jeffrey Parker. 

Concentrations Of Credit Risk

Concentrations Of Credit Risk	12 Months Ended
	Dec. 31, 2020
Concentrations Of Credit Risk [Abstract]
Concentration Of Credit Risk	1 6 . CONCENTRATIONS OF CREDIT RISK  Financial instruments that potentially subject us to a concentration of credit risk principally consist of cash and cash equivalents. Cash and cash equivalents are primarily held in bank accounts and overnight investments. At times our cash balances on deposit with banks may exceed the balance insured by the F.D.I.C. 

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	17. SUBSEQUENT EVENTS  Equity and Debt Financings In January 2021, we consummated the sale, on a private placement basis, of 2,976,430 shares of our common stock at a price of $0.35 per share to accredited investors for aggregate proceeds of approximately $1.0 million. The securities purchase agreements include contingent payment rights identical to the CPRs issued in 2020 (see “unsecured contingent payment obligations” at Note 9). Approximately $0.4 million in proceeds for this transaction was received as of December 31, 2020 and recorded as an accrued liability until the consummation of the transaction (see Note 7). We entered into registration rights agreements with the investors pursuant to which we will register the shares. We have committed to file the registration statement by April 15, 2021 and to cause the registration statement to become effective by June 30, 2021. The registration rights agreements provide for liquidated damages upon the occurrence of certain events including failure by us to file the registration statement or cause it to become effective by the deadlines set forth above. The amount of the liquidated damages is 1.0% of the aggregate subscription upon the occurrence of the event, and monthly thereafter, up to a maximum of 6% , or approximately $0.06 million. In March 2021, we consummated the sale, on a private placement basis of 3,230,942 shares of our common stock and 1,619,289 warrants at a price of $1.29 per common share to accredited investors for aggregate proceeds of approximately $4.2 million. The warrants have an exercise price of $1.75 per share and expire in March 2026. We entered into registration rights agreements with the investors pursuant to which we will register the shares. We have committed to file the registration statement within 30 days and to cause the registration statement to become effective within 90 days. The registration rights agreements provide for liquidated damages upon the occurrence of certain events including failure by us to file the registration statement or cause it to become effective by the deadlines set forth above. The amount of the liquidated damages is 1.0% of the aggregate subscription upon the occurrence of the event, and monthly thereafter, up to a maximum of 6% , or approximately $0.25 million. The majority of the proceeds from this transaction were used to satisfy our obligations to Mintz (see “Mintz Agreement” below).  Share Based Compensation Arrangements On January 11, 2021, the Board amended the 2019 Long-Term Incentive Plan to increase the number of shares of common stock reserved for issuance under the 2019 Plan from 12 million to 27 million shares. The Board also approved grants, under the 2019 Plan, of two -year options, with an exercise price of $0.54 per share, vesting in 8 equal quarterly installments commencing on March 31, 2021 and expiring on January 11, 2026. The grants under the 2019 Plan included an option to purchase 8,000,000 shares granted to Jeffrey Parker, an option to purchase 1,000,000 shares granted to Cynthia French, an option to purchase 380,000 shares to each of the three non-employee directors, and options to purchase an aggregate of 2,900,000 shares granted to other key employees.  On January 25, 2021, we amended our business consulting and retention agreement with Chelsea to increase the compensation for services over the remaining term and to extend the term of the agreement through February 2024. As consideration for the amended agreement, we issued 500,000 shares of unregistered common stock in exchange for a nonrefundable retainer for services valued at approximately $0.33 million. The value of the stock issued is being recognized as consulting expense over the term of the agreement.  On March 9, 2021, we granted approximately 32,000 shares under our 2019 Long-Term Incentive Plan to a consultant for business communications services over a one -year term valued at approximately $0.05 million.  Warrant and Option Exercises During the three months ended March 31, 2021, we received aggregate proceeds of $0. 4 million from the exercise of outstanding options and warrants at an average exercise price of $0.16 per share.  Mintz Agreement As of December 31, 2020, we had approximately $3.1 million in accounts payable to Mintz and an outstanding balance of approximately $0.03 million on a secured note payable to Mintz for legal fees and expenses. In addition, we had approximately $3.6 million in disputed legal fees and expenses billed by Mintz that we treated as a loss contingency that was not probable as of December 31, 2020 and 2019 and accordingly, for which we recognized no expense in the consolidated financial statements. In March 2021, we entered into an agreement with Mintz to satisfy our outstanding obligations and reduce any future contingency fees payable to Mintz. On March 2 9 , 2021, we paid Mintz a lump-sum payment of $3.0 million in satisfaction of our outstanding obligations to Mintz including the Mintz note, our accounts payable to Mintz, and all disputed and unrecorded billings. Mintz waived all past defaults on the Mintz note and agreed to a significant reduction in future success fees payable to Mintz from patent-related proceeds.  Legal Proceedings On March 26, 2021, the district court in the Middle District of Florida, Orlando Division, issued an order that, among other things, postponed our trial date in ParkerVision v. Qualcomm citing backlog due to the pandemic as a factor. A new trial date has not yet been set but is unlikely to be scheduled prior to November or December 2021 according to the court.

Significant Accounting Polici_2

Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Our consolidated financial statements are prepared in accordance with generally accepted accounting principles in the U.S. (“ GAAP ”). Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The consolidated financial statements include the accounts of ParkerVision, Inc. and our wholly-owned German subsidiary, ParkerVision GmbH, after elimination of all intercompany transactions and accounts.
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. The more significant estimates made by us include projected future cash flows and risk-adjusted discount rates for estimating the fair value of our contingent payment obligations, the volatility and estimated lives of share-based awards used in the estimate of the fair market value of share-based compensation, the assessment of recoverability of long-lived assets, the amortization periods for intangible and long-lived assets, and the valuation allowance for deferred taxes. Actual results could differ from the estimates made. We periodically evaluate estimates used in the preparation of the financial statements for continued reasonableness. Appropriate adjustments, if any, to the estimates used are made prospectively based upon such periodic evaluation.
Cash and Cash Equivalents	 Cash and Cash Equivalents We consider cash and cash equivalents to include cash on hand, interest-bearing deposits, overnight repurchase agreements and investments with original maturities of three months or less when purchased.
Inventory	  Inventory Inventory is stated at the lower of actual cost, as determined under the first-in, first-out method, or estimated net realizable value. We review our inventory for estimated obsolescence or unmarketable inventory and write down inventory for the difference between cost and estimated market value based upon assumptions about future demand. Future demand is affected by market conditions, technological obsolescence, new products and strategic plans, each of which is subject to change. Due to the decision to discontinue Milo product sales in the fourth quarter of 2019, a full reserve was recorded against the remaining inventory on hand at December 31, 2019. All remaining inventory was disposed of during the year ended December 31, 2020.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is determined using the straight-line method over the following estimated useful lives:    Manufacturing and office equipment 5 -7 years  Leasehold improvements Shorter of useful life or remaining life of lease  Furniture and fixtures 7 years  Computer equipment and software 3 -5 years  The cost and accumulated depreciation of assets sold or retired are removed from their respective accounts, and any resulting net gain or loss is recognized in the accompanying consolidated statements of comprehensive loss. The carrying value of long-lived assets is reviewed on a regular basis for the existence of facts, both internally and externally, that may suggest impairment. Recoverability of assets to be held and used is measured by comparing the carrying amount of an asset to the estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the assets exceeds its estimated undiscounted future net cash flows, an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the assets.
Intangible Assets	Intangible Assets We capitalize outside legal costs and agency filing fees incurred in connection with securing the rights to our intellectual property. Patents, copyrights and other intangible assets are amortized using the straight-line method over their estimated period of benefit. We estimate the economic lives of our patents and copyrights to be fifteen to twenty years. Management evaluates the recoverability of intangible assets periodically and takes into account events or circumstances that may warrant revised estimates of useful lives or that may indicate impairment exists. As part of our ongoing patent maintenance program, we will, from time to time, abandon a particular patent if we determine fees to maintain the patent exceed its expected recoverability. The cost and accumulated amortization of abandoned intangible assets are removed from their respective accounts, and any resulting net loss is recognized in selling, general and administrative expenses in the accompanying consolidated statements of comprehensive loss.
Contingent Payment Obligations	Contingent Payment Obligations We have accounted for our secured and unsecured contingent payment obligations as long-term debt in accordance with Accounting Standards Codification (“ ASC ”) 470-10-25, “Sales of Future Revenues or Various other Measures of Income.” Our payment obligations are contingent upon the receipt of proceeds from patent enforcement and/or patent monetization actions. We have elected to measure our contingent payment obligations at their estimated fair values in accordance with ASC 825, “Financial Instruments” based on the variable and contingent nature of the repayment provisions. We have determined that the fair value of our secured and unsecured contingent payment obligations falls within Level 3 in the fair value hierarchy, which involves significant estimates, and assumptions including projected future patent-related proceeds and the risk-adjusted rate for discounting future cash flows (see Note 10). Actual results could differ from the estimates made. Changes in fair value, including the component related to imputed interest, are included in the accompanying consolidated statements of comprehensive loss under the heading “Change in fair value of contingent payment obligations.”
Leases	Leases We adopted ASC 842, “Leases” as of January 1, 2019 which requires the recognition of lease right-of-use (“ ROU ”) assets and lease liabilities on our consolidated balance sheets for finance and operating leases with initial lease terms of more than 12 months. We elected to use the effective date as the initial application date. ASC 842 provides a number of practical expedients in transition and we elected the package of practical expedients which permits us not to reassess under the new standard our prior conclusions about lease identification, lease classification and treatment of initial direct costs. The adoption of this new standard resulted in the recognition of operating lease ROU assets and operating lease liabilities of approximately $0.56 million and $0.60 million, respectively, primarily related to our facilities leases. Refer to Note 8 for additional disclosures related to our leases.  At inception of a lease, we determine if an arrangement contains a lease and whether that lease meets the classification criteria of a finance or operating lease. Some of our lease arrangements contain lease components (e.g. minimum rent payments) and non-lease components (e.g. services). For certain equipment leases, we account for lease and non-lease components separately based on a relative fair market value basis. For all other leases, we account for the lease and non-lease components (e.g. common area maintenance) on a combined basis.  For operating leases with terms greater than 12 months, we record the ROU asset and lease obligation at the present value of lease payments over the term using the implicit interest rate, when readily available, or our incremental borrowing rate for collateralized debt based on information available at the lease commencement date. Certain of our leases include rental escalation clauses, renewal options and/or termination options that are factored into our determination of lease payments when it is reasonably certain that the option will be exercised. We do not recognize ROU assets and lease liabilities for leases with terms at inception of twelve months or less.  Finance leases are included in property and equipment and other accrued expenses on the consolidated balance sheets. Finance leases are recorded as an asset and an obligation at an amount equal to the present value of the minimum lease payments during the lease term. Amortization expense and interest expense associated with finance leases are included in selling, general, and administrative expense and interest expense, respectively, on the consolidated statements of comprehensive loss.
Convertible Debt	Convertible Debt We have issued debt that is convertible, at the holder’s option, into shares of our common stock at fixed conversion prices. Certain of the convertible notes were issued with conversion prices that were below market value of our common stock on the closing date resulting in a beneficial conversion feature which we recorded to equity with a corresponding discount to the debt. The discount is amortized over the life of the notes as interest expense.  In August 2020, the Financial Accounting Standards Board issued ASU 2020-06 "Debt - Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity." This ASU simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. Consequently, more convertible debt instruments will be reported as a single liability instrument with no separate accounting for embedded conversion features. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception, which will permit more equity contracts to qualify for the exception. The ASU also simplifies the diluted earnings per share (EPS) calculation in certain areas. The ASU is effective for fiscal years beginning after December 15, 2021 for accelerated filers and for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, for smaller reporting companies. Early adoption is permitted for fiscal years beginning after December 15, 2020. The ASU provides for a modified retrospective method of adoption whereby the guidance is applied to transactions outstanding at the beginning of the fiscal year of adoption with the cumulative effect of the change being recorded as an adjustment to beginning retained earnings.  We plan to adopt ASU 2020-06, using the modified retrospective method, as of January 1, 2021. Adoption of ASU 2020-06 will result in an increase to our long-term debt of approximately $0.8 million, a decrease in additional paid-in-capital of approximately $1.1 million, and an adjustment to our beginning retained deficit of $0.3 million resulting from the elimination of the previously recognized beneficial conversion feature as a debt discount.
Revenue Recognition	Revenue Recognition We account for revenue under ASC 606, “Revenue from Contracts with Customers” which implements a common revenue standard that clarifies the principles for recognizing revenue. This revenue recognition model provides a five-step analysis in determining when and how revenue is recognized.  We expect to derive future revenue from licensing of our intellectual property and settlements from patent infringement disputes. The timing of revenue recognition and the amount of revenue recognized depends upon a variety of factors, including the specific terms of each arrangement and the nature of our deliverables and obligations. In general, we recognize revenue when the performance obligations to our customers have been met. The consideration received from patent license and settlement agreements is allocated to the various elements of the arrangement to the extent the revenue recognition differs between the elements of the arrangement. Elements related to past and future royalties as well as elements related to settlement will be recorded as revenue in our consolidated statements of comprehensive loss when our performance obligations related to each element have been met.  For the year ended December 31, 2019, we recognized revenue from the sale of products. For product sales, the performance obligation is generally met at the time product is delivered to the customer. Estimated product returns are deducted from revenue and recorded as a liability. Revenue from the sale of our products includes shipping and handling charged to the customer. Product revenue is recorded net of sales tax collected from customers, discounts, and actual and estimated future returns.
Research and Development Expenses	Research and Development Expenses Research and development costs are expensed as incurred and include salaries and benefits for employees engaged in research and development activities, costs paid to third party contractors, prototype expenses, an allocated portion of facilities costs, maintenance costs for software development tools, and depreciation.
Accounting for Share-Based Compensation	Accounting for Share-Based Compensation We have various share-based compensation programs which provide for equity awards including stock options, restricted stock units (“ RSUs ”) and restricted stock awards (“ RSAs ”). We calculate the fair value of employee share-based equity awards on the date of grant and recognize the calculated fair value as compensation expense over the requisite service periods of the related awards. We estimate the fair value of stock option awards using the Black-Scholes option valuation model. This valuation model requires the use of highly subjective assumptions and estimates including how long employees will retain their stock options before exercising them and the volatility of our common stock price over the expected life of the equity award. Such estimates, and the basis for our conclusions regarding such estimates, are outlined in detail in Note 14. Estimates of fair value are not intended to predict actual future events or the value ultimately realized by persons who receive equity awards. We account for forfeitures of share-based awards as they occur.  As of January 1, 2019, we adopted ASU 2018-07, "Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting." The amendments in this update simplify the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. At the time of adoption, we did not have any awards to nonemployees that would require reassessment and therefore the adoption of ASU 2018-07 did not impact our consolidated financial statements.
Income Taxes	  Income Taxes The provision for income taxes is based on loss before taxes as reported in the accompanying consolidated statements of comprehensive loss. Deferred tax assets and liabilities are recognized for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on differences between the financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established to reduce deferred tax assets when, based on available objective evidence, it is more likely than not that the benefit of such assets will not be realized. Our deferred tax assets exclude unrecognized tax benefits which do not meet a more-likely-than-not threshold for financial statement recognition for tax positions taken or expected to be taken in a tax return.  As of January 1, 2019, we adopted ASU 2018-02, “Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” The amendments in this update allow a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act. We have no stranded tax effects included in our other comprehensive loss and therefore the adoption of ASU 2018-02 did not impact our consolidated financial statements.
Loss per Common Share	Loss per Common Share Basic loss per common share is determined based on the weighted-average number of common shares outstanding during each year. Diluted loss per common share is the same as basic loss per common share as all potential common shares are excluded from the calculation, as their effect is anti-dilutive.  The number of shares underlying outstanding options, warrants, unvested RSUs, and convertible notes at December 31, 2020 and 2019 were as follows (in thousands):    2020 2019  Options outstanding 12,240 11,410  Warrants outstanding 12,850 12,150  Unvested RSUs 187 -  Shares underlying convertible notes 23,557 20,846  48,834 44,406   These potential shares were excluded from the computation of diluted loss per share as their effect would have been anti-dilutive.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Schedule Of Property And Equipment Useful Lives	   Manufacturing and office equipment 5 -7 years  Leasehold improvements Shorter of useful life or remaining life of lease  Furniture and fixtures 7 years  Computer equipment and software 3 -5 years 
Summary Of Anti-Dilutive Shares	   2020 2019  Options outstanding 12,240 11,410  Warrants outstanding 12,850 12,150  Unvested RSUs 187 -  Shares underlying convertible notes 23,557 20,846  48,834 44,406  

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2020
Inventories [Abstract]
Schedule Of Inventory Reserves	   2020 2019  Inventory reserves at beginning of year $ 550 $ 982  Impairment charges - 6  Write down of impaired inventories - (438)  Disposal of inventory (550) -  Inventory reserves at end of year $ - $ 550  

Prepaid Expenses (Tables)

Prepaid Expenses (Tables)	12 Months Ended
	Dec. 31, 2020
Prepaid Expenses [Abstract]
Schedule Of Prepaid Expenses	   2020 2019  Prepaid services $ 408 $ 221  Prepaid bonds for German statutory costs 142 188  Prepaid insurance 21 62  Prepaid licenses, software tools and support 11 17  Other prepaid expenses 17 17  $ 599 $ 505  

Property And Equipment, Net (Ta

Property And Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2020
Property And Equipment, Net [Abstract]
Schedule Of Property And Equipment, Net	   2020 2019  Equipment and software $ 218 $ 260  Leasehold improvements 19 33  Furniture and fixtures 30 43  267 336  Less accumulated depreciation (237) (266)  $ 30 $ 70  

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Intangible Assets [Abstract]
Schedule Of Intangible Assets	   2020 2019   Patents and copyrights $ 14,948 $ 16,612  Less accumulated amortization (12,778) (13,734)  $ 2,170 $ 2,878  
Schedule Of Future Amortization Expense	   2021 $ 358  2022 321  2023 283  2024 270  2025 231  2026 and thereafter 707  Total $ 2,170  

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2020
Accrued Liabilities [Abstract]
Other Accured Expenses	  2020 2019  Advances $ 882 $ 500  Board compensation - 413  Other accrued expenses 54 168  $ 936 $ 1,081  

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Supplemental Cash Flow Information	  Year Ended Year Ended  December 31, December 31,  2020 2019  Cash paid for amounts included in the measurement of lease liabilities:  Operating cash flows from operating leases $ 315 $ 314  Operating cash flows from finance leases - -  Financing cash flows from finance leases - 1   Non-cash activity  Right-of-use assets obtained in exchange for operating lease liabilities - 563  Assets obtained in exchange for finance lease liabilities - -  
Supplemental Information	    December 31, December 31,  2020 2019  Weighted-average remaining lease term (in years):  Operating leases 1.7 2.7  Finance leases - 0.3  Weighted average discount rate  Operating leases (1) 12.1% 12.0%  Finance leases - 8.7%  Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019.
Future Maturities of Lease Liabilities	   Operating Leases Finance Leases  2021 $ 175 $ -  2022 166 -  2023 4 -  Thereafter - -  Total undiscounted lease payments 345 -  Less: imputed interest (40) -  Present value of lease liabilities 305 -  Less: current obligations under leases (146) -  Long-term lease obligations $ 159 $ -  

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Instrument [Line Items]
Summary Of Aggregate Maturities	    2021 $ 191  2022 832  Total $ 1,023  
Schedule Of Convertible Notes Payable	   Fixed Effective  Conversion Interest December 31,  Description Rate Rate 1 Maturity Date 2020 2019  Convertible notes dated September 10, 2018 $0.40 23.4% September 7, 2023 $ 600 $ 700  Convertible notes dated September 19, 2018 $0.57 10.2% September 19, 2023 425 425  Convertible notes dated February/March 2019 $0.25 8.0% February 28, 2024 to March 13, 2024 1,300 1,300  Convertible notes dated June/July 2019 $0.10 8.0% June 7, 2024 to July 15, 2024 340 390  Convertible notes dated July 18, 2019 $0.08 46.1% July 18, 2024 700 700  Convertible notes dated September 13, 2019 $0.10 25.9% September 13, 2024 50 50  Convertible notes dated January 8, 2020 $0.13 20.3% January 8, 2025 450 -  Total principal balance 3,865 3,565  Less unamortized discount 847 832  $ 3,018 $ 2,733  
Secured Debt [Member]
Debt Instrument [Line Items]
Reconciliation Of Secured And Unsecured Contingent Obligation At Fair Value	    2020 2019  Secured contingent payment obligation, beginning of year $ 26,651 $ 25,557  Change in fair value 6,406 1,094  Secured contingent payment obligation, end of year $ 33,057 $ 26,651  
Unsecured Debt [Member]
Debt Instrument [Line Items]
Reconciliation Of Secured And Unsecured Contingent Obligation At Fair Value	  2020 2019  Unsecured contingent payment obligations, beginning of period $ - $ -  Reclassification of other liabilities 1,003 -  Issuance of contingent payment rights 2,258 -  Change in fair value 1,961 -  Unsecured contingent payment obligations, end of period $ 5,222 $ -  

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Measurements [Abstract]
Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis	   Fair Value Measurements  Total Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3)  December 31, 2020:  Liabilities:  Secured contingent payment obligation $ 33,057 $ - $ - $ 33,057  Unsecured contingent payment obligations 5,222 - - 5,222    December 31, 2019:  Liabilities:  Secured contingent payment obligation 26,651 - - 26,651  
Quantitative Information	   Secured Contingent Payment Obligation Unsecured Contingent Payment Obligations  Unobservable Inputs Low Weighted Average High Low Weighted Average High   Estimated undiscounted cash outflows (in millions) $ 0.0 $ 46.1 $ 70.2 $ 0.0 $ 7.3 $ 9.7  Duration (in years) 1.0 2.5 3.5 1.0 2.5 3.5  Estimated probabilities 5% 23% 25% 25% 25% 25%  

Income Taxes And Tax Status (Ta

Income Taxes And Tax Status (Tables)	12 Months Ended
	Dec. 31, 2020
Income Taxes And Tax Status [Abstract]
Schedule Of Effective Income Tax Rate Reconciliation	   2020 2019  Tax benefit at statutory rate $ (4,111) $ (1,985)  State tax benefit (842) (407)  Increase in valuation allowance 4,307 2,341  Other 646 51  $ - $ -  
Schedule Of Deferred Tax Assets And Liabilities	   2020 2019  Gross deferred tax assets:  Net operating loss carry-forward $ 80,848 $ 83,865  Research and development credit carry-forward 6,603 7,608  Stock compensation 122 (28)  Patents and other 1,466 1,479  Contingent payment obligations 5,235 3,119  Inventories - 139  Fixed assets 54 3  Accrued liabilities 64 200  Lease liabilities 77 142  Other - 3  94,469 96,530  Less valuation allowance (94,245) (96,320)  224 210  Gross deferred tax liabilities:  Convertible debt (224) (210)  (224) (210)  Net deferred tax asset $ - $ -  
Schedule Of Unrecognized Tax Benefits Roll Forward	   2020 2019  Unrecognized tax benefits – beginning of year $ 927 $ 927  Unrecognized tax benefits – end of year $ 927 $ 927  

Stock Authorization And Issua_2

Stock Authorization And Issuance (Tables)	12 Months Ended
	Dec. 31, 2020
Stock Authorization And Issuance [Abstract]
Summary Of Equity Offerings	   Date Transaction # of Common Shares/ Units Sold Average Price per Share/Unit # of Warrants Issued (in 000’s) Average Exercise Price per Warrant Net Proceeds (1)  January 2020 Private placement of common stock 1,335 $0.13 - - $ 177  February 2020 Warrant amendment - - 5,000 $0.74 $ -  March 2020 Private placement of common stock, amended to add CPR 2,571 $0.35 - - $ 900  April 2020 to December 2020 Private placement of common stock with CPRs 10,858 $0.35 - - $ 3,724  (1) After deduction of applicable offering costs.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule Of Share-Based Compensation Expense Included In Statements Of Operations	   2020 2019  Research and development expense $ - $ 5  Selling, general, and administrative expense 1,244 584  Total share-based compensation expense $ 1,244 $ 589  
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary Of Options Activity	   Shares Weighted- Average Exercise Price Weighted-Average Remaining Contractual Term Aggregate Intrinsic Value ($)  Outstanding at beginning of year 11,410 $ 0.33  Granted 843 0.31  Exercised - -  Forfeited/Expired (13) 38.86  Outstanding at end of year 12,240 0.28 5.5 years $ 3,401  Vested at end of year 9,490 $ 0.31 5.5 years $ 2,578  
Summary Of Valuation Assumptions	   Year ended December 31,  2020 2019  Expected option term 1 5 years 5 years  Expected volatility factor 2 127.4% to 135.3% 119.1%  Risk-free interest rate 3 0.33% to 1.63% 1.6%  Expected annual dividend yield 0% 0%  1 The expected term was generally determined based on historical activity for grants with similar terms and for similar groups of employees and represents the period of time that options are expected to be outstanding. For employee options, groups of employees with similar historical exercise behavior are considered separately for valuation purposes. 2 The stock volatility for each grant is measured using the weighted average of historical daily price changes of our common stock over the most recent period equal to the expected option life of the grant. 3 The risk-free interest rate for periods equal to the expected term of the share option is based on the U.S. Treasury yield curve in effect at the measurement date.
Summary Of Options And Warrants By Exercise Price Range	   Options Outstanding Options Vested  Range of Exercise Prices Number Outstanding at December 31, 2020 Wtd. Avg. Exercise Price Wtd. Avg. Remaining Contractual Life Number Exercisable at December 31, 2020 Wtd. Avg. Exercise Price Wtd. Avg. Remaining Contractual Life  $0.171 - $0.33 11,318 $ 0.18 5.6 8,624 $ 0.18 5.6  $0.50 - $0.60 513 0.59 5.0 457 0.60 4.8  $1.98 - $2.13 381 2.02 3.4 381 2.02 3.4  $13.80 28 13.80 0.5 28 13.80 0.5  12,240 $ 0.28 5.5 9,490 $ 0.31 5.5  
Restricted Stock Award And Restricted Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary Of Restricted Stock Activity	   Non-vested Shares  Shares Weighted-Average Grant Date Fair Value  Non-vested at beginning of year - $ -  Granted 1,016 0.31  Vested (829) 0.31  Forfeited - -  Non-vested at end of year 187 $ 0.33  

Significant Accounting Polici_4

Significant Accounting Policies (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)segment	Dec. 31, 2019USD ($)
Significant Accounting Policies [Line Items]
Operating segments | segment	1
Reportable segments | segment	1
Operating lease right-of-use assets	$ 10	$ 283
Operating Lease, Liability	40
Long-term Debt	1,023
Accumulated deficit	(421,361)	(401,783)
Accounting Standards Update 2016-02 [Member]
Significant Accounting Policies [Line Items]
Operating lease right-of-use assets		560
Operating Lease, Liability		$ 600
Accounting Standards Update 2020-06 [Member]
Significant Accounting Policies [Line Items]
Long-term Debt	800
Accumulated deficit	300
Additional Paid in Capital	$ (1,100)
Patents And Copyrights [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Intangible assets, useful life	15 years
Patents And Copyrights [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Intangible assets, useful life	20 years

Significant Accounting Polici_5

Significant Accounting Policies (Schedule Of Property And Equipment Useful Lives) (Details)	12 Months Ended
	Dec. 31, 2020
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Useful life	Shorter of useful life or remaining life of lease
Furniture And Fixtures [Member]
Property, Plant and Equipment [Line Items]
Useful life	7 years
Minimum [Member] | Manufacturing And Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Useful life	5 years
Minimum [Member] | Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum [Member] | Manufacturing And Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Useful life	7 years
Maximum [Member] | Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Useful life	5 years

Significant Accounting Polici_6

Significant Accounting Policies (Summary Of Anti-Dilutive Shares) (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	48,834	44,406
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	12,240	11,410
Warrants Outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	12,850	12,150
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	187
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares	23,557	20,846

Liquidity And Going Concern (De

Liquidity And Going Concern (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liquidity And Working Capital [Line Items]
Net loss		$ (19,578)	$ (9,453)
Net cash used in operating activities		(4,777)	(3,373)
Accumulated deficit		(421,361)	(401,783)
Net working capital		3,800
Cash and cash equivalents, beginning of period		$ 1,627	$ 57
Subsequent Event [Member]
Liquidity And Working Capital [Line Items]
Payment to settle outstanding accounts and notes payable for litigation costs	$ 3,000
Proceeds from debt and equity securities and warrant and option exercises	$ 5,600

Inventories (Narrative) (Detail

Inventories (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Inventories [Abstract]
Inventory Valuation Reserves		$ 550	$ 982

Inventories (Schedule Of Invent

Inventories (Schedule Of Inventory Reserves) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Inventories [Abstract]
Inventory reserves at beginning of year	$ 550	$ 982
Impairment charges		6
Write down of impaired inventories		(438)
Disposal of inventory	(550)
Inventory reserves at end of year		$ 550

Prepaid Expenses (Details)

Prepaid Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Prepaid Expenses [Abstract]
Prepaid services	$ 408	$ 221
Prepaid bonds for German statutory costs	142	188
Prepaid insurance	21	62
Prepaid licenses, software tools and support	11	17
Other prepaid expenses	17	17
Prepaid expenses	$ 599	$ 505

Property And Equipment, Net (Na

Property And Equipment, Net (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Assets held for sale			$ (70)
Gain (loss) on sale of assets held for sale and impairment		$ (40)
Corporate Headquarters [Member]
Property, Plant and Equipment [Line Items]
Gain (loss) on sale of assets held for sale	$ (20)	10
Property And Equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 30	$ 40

Property And Equipment, Net (Sc

Property And Equipment, Net (Schedule Of Property And Equipment, Net) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment	$ 267	$ 336
Less accumulated depreciation	(237)	(266)
Property, Plant and Equipment, Net, Total	30	70
Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	218	260
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	19	33
Furniture And Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 30	$ 43

Intangible Assets (Narrative) (

Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Intangible Assets [Abstract]
Amortization expense	$ 0.4	$ 0.6
Loss on disposal	$ (0.3)	$ (0.4)

Intangible Assets (Schedule Of

Intangible Assets (Schedule Of Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Intangible Assets [Abstract]
Patents and copyrights	$ 14,948	$ 16,612
Less accumulated depreciation	(12,778)	(13,734)
Total	$ 2,170	$ 2,878

Intangible Assets (Schedule O_2

Intangible Assets (Schedule Of Future Amortization Expense) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Intangible Assets [Abstract]
2021	$ 358
2022	321
2023	283
2024	270
2025	231
2026 and thereafter	707
Total	$ 2,170	$ 2,878

Accrued Liabilities (Narrative)

Accrued Liabilities (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued Liabilities [Abstract]
Amount Received From Investors	$ 400
Board compensation		$ 413
Aggregate grant-date fair value	$ 100

Accrued Liabilities (Other Accu

Accrued Liabilities (Other Accured Expenses) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued Liabilities [Abstract]
Advances	$ 882	$ 500
Board compensation		413
Other accrued expenses	54	168
Accrued Liabilities	$ 936	$ 1,081

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property Subject to or Available for Operating Lease [Line Items]
Operating lease cost	$ 100	$ 400
Lease liability	40
Corporate Office [Member] | Lake Mary Florida [Member]
Property Subject to or Available for Operating Lease [Line Items]
Impairment loss	$ 200

Leases (Supplemental Cash Flow

Leases (Supplemental Cash Flow Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating cash flows from operating leases	$ 315	$ 314
Operating cash flows from finance leases
Financing cash flows from finance leases		1
Right-of-use assets obtained in exchange for operating lease liabilities		563
Assets obtained in exchange for finance lease liabilities

Leases (Supplemental Informatio

Leases (Supplemental Information) (Details)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	1 year 8 months 12 days	2 years 8 months 12 days
Finance Lease, Weighted Average Remaining Lease Term		3 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent	12.10%	12.00%
Finance Lease, Weighted Average Discount Rate, Percent		8.70%

Leases (Future Maturities of Le

Leases (Future Maturities of Lease Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2021	$ 175
2022	166
2023	4
Total undiscounted lease payments	345
Less: imputed interest	(40)
Present value of lease liabilities	305
Less: current obligations under leases	(146)	$ (250)
Long-term lease obligations	$ 159	$ 305

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details)	1 Months Ended	12 Months Ended		60 Months Ended
	May 31, 2020USD ($)	Dec. 31, 2020USD ($)item$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2020USD ($)item$ / shares	Mar. 31, 2020USD ($)
Debt Instrument [Line Items]
Change in fair value of contingent payment obligations		$ (8,367,000)	$ (1,094,000)
Fair value of note payable		900,000		$ 900,000
Brickell [Member]
Debt Instrument [Line Items]
Debt Instrument, Estimated Minimum Return		42,000,000	39,000,000
Secured Debt [Member] | Brickell [Member]
Debt Instrument [Line Items]
Repayments of Debt				3,300,000
Proceeds from debt		$ 0	$ 0	$ 18,000,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate		8.00%		8.00%
Shares issued | shares		710,000	1,600,000
Note Payable To A Related Party [Member] | Unsecured Debt [Member] | Sterne, Kessler, Goldstein & Fox, PLLC [Member]
Debt Instrument [Line Items]
Debt		$ 800,000		$ 800,000
Interest expense		$ 30,000	$ 40,000
Note Payable To A Related Party [Member] | Secured Debt [Member] | Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. [Member]
Debt Instrument [Line Items]
Interest rate		12.00%		12.00%
Repayments of Debt		$ 1,200,000
Transfer of capital stock		50.00%
Accrued interest		$ 30,000		$ 30,000
Notes payable		$ 3,100,000		$ 3,100,000
Promissory Notes [Member] | Unsecured Debt [Member] | Sterne, Kessler, Goldstein & Fox, PLLC [Member]
Debt Instrument [Line Items]
Interest rate		4.00%		4.00%
Debt payment per month		$ 10,000
Final balloon payment		$ 680,000		$ 680,000
Maturity date		Apr. 30, 2022
Promissory Notes [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Proceeds from debt		$ 450,000	2,440,000
Beneficial conversion feature		170,000	550,000
Interest expense		470,000	320,000
Amortization		170,000	120,000
Contractual interest		300,000	200,000
Outstanding principal converted		$ 150,000	$ 100,000
Shares issued | shares		750,000	250,000
Conversion price | $ / shares		$ 0.20	$ 0.40	$ 0.20
Aggregate common stock | item		23,600,000
Debt, term		5 years
Promissory Notes [Member] | Convertible Debt [Member] | Measurement Input, Prepayment Rate [Member] | Debt Instrument, Redemption, Period One [Member]
Debt Instrument [Line Items]
Measurement input | item		0.25		0.25
Promissory Notes [Member] | Convertible Debt [Member] | Measurement Input, Prepayment Rate [Member] | Debt Instrument, Redemption, Period Two [Member]
Debt Instrument [Line Items]
Measurement input | item		0.20		0.20
Promissory Notes [Member] | Convertible Debt [Member] | Measurement Input, Prepayment Rate [Member] | Debt Instrument, Redemption, Period Three [Member]
Debt Instrument [Line Items]
Measurement input | item		0.15		0.15
Promissory Notes [Member] | Convertible Debt [Member] | Measurement Input, Prepayment Rate [Member] | Debt Instrument, Redemption, Period Four [Member]
Debt Instrument [Line Items]
Measurement input | item		0.10		0.10
Promissory Notes [Member] | Convertible Debt [Member] | Measurement Input, Default Rate [Member]
Debt Instrument [Line Items]
Measurement input | item		0.12		0.12
Short Term Promissory Notes [Member]
Debt Instrument [Line Items]
Interest rate		20.00%		20.00%
Short Term Promissory Notes [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Repayments of Debt		$ 230,000
Accrued interest		40,000		$ 40,000
Interest expense		$ 10,000	$ 30,000
Shares issued | shares		1,740,426
Convertible Debt, July 18, 2019 [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate		7.50%		7.50%
Contingent Payment Obligation [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Common stock issued		$ 3,800,000
Termination payment		2,700,000		$ 2,700,000	$ 5,000,000
Contingent Payment Obligation [Member] | Unsecured Debt [Member] | Termination Fee [Member]
Debt Instrument [Line Items]
Fair value of payment obligation		600,000	400,000	600,000
Measurement input		$ 600,000	$ 400,000	600,000
Paycheck Protection Program Loan [Member]
Debt Instrument [Line Items]
Interest rate	1.00%
Debt payment per month	$ 8,000
Maturity date		May 3, 2022
Proceeds from debt	$ 200,000
Contingent Payment Rights [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Common stock issued		$ 1,800,000
Proceeds from debt		900,000
Change in fair value of contingent payment obligations		400,000
Fair value of payment obligation		2,500,000		2,500,000
Measurement input		2,500,000		2,500,000
Contingent Payment Rights [Member] | Unsecured Debt [Member] | Measurement Input, Quotient [Member]
Debt Instrument [Line Items]
Fair value of payment obligation		10,000,000		10,000,000
Measurement input		10,000,000		10,000,000
Contingent Payment Rights [Member] | Unsecured Debt [Member] | Measurement Input, Investors Subscription [Member]
Debt Instrument [Line Items]
Fair value of payment obligation		10,000,000		10,000,000
Measurement input		10,000,000		10,000,000
Contingent Payment Rights [Member] | Unsecured Debt [Member] | Measurement Input, Investors Subscription, Aggregate [Member]
Debt Instrument [Line Items]
Fair value of payment obligation		4,700,000		4,700,000
Measurement input		$ 4,700,000		$ 4,700,000
Minimum [Member] | Brickell [Member]
Debt Instrument [Line Items]
Percentage of proceeds payment		55.00%
Maximum [Member] | Brickell [Member]
Debt Instrument [Line Items]
Percentage of proceeds payment		100.00%

Long-Term Debt (Summary Of Aggr

Long-Term Debt (Summary Of Aggregate Maturities) (Details) $ in Thousands	Dec. 31, 2020USD ($)
Long-Term Debt [Abstract]
2021	$ 191
2022	832
Convertible notes, net	$ 1,023

Long-Term Debt (Schedule Of Con

Long-Term Debt (Schedule Of Convertible Notes Payable) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Convertible notes, net	$ 3,018	$ 2,733
Convertible Debt [Member]
Debt Instrument [Line Items]
Total principal balance	3,865	3,565
Less Unamortized discount	847	832
Convertible notes, net	$ 3,018	2,733
Convertible Debt [Member] | Convertible Notes Dated September 10, 2018 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.40
Effective Interest Rate	23.40%
Maturity Date	Sep. 7, 2023
Total principal balance	$ 600	700
Convertible Debt [Member] | Convertible Note Dated September 19, 2018 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.57
Effective Interest Rate	10.20%
Maturity Date	Sep. 19, 2023
Total principal balance	$ 425	425
Convertible Debt [Member] | Convertible Notes Dated February/March 2019 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.25
Effective Interest Rate	8.00%
Total principal balance	$ 1,300	1,300
Convertible Debt [Member] | Convertible Note Dated June/July 2019 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.10
Effective Interest Rate	8.00%
Total principal balance	$ 340	390
Convertible Debt [Member] | Convertible Note Dated July 18, 2019 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.08
Effective Interest Rate	46.10%
Maturity Date	Jul. 18, 2024
Total principal balance	$ 700	700
Convertible Debt [Member] | Convertible Note Dated September 13, 2019 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.10
Effective Interest Rate	25.90%
Maturity Date	Sep. 13, 2024
Total principal balance	$ 50	$ 50
Convertible Debt [Member] | Convertible Notes Dated January 8, 2020 [Member]
Debt Instrument [Line Items]
Fixed Conversion Rate	$ 0.13
Effective Interest Rate	20.30%
Maturity Date	Jan. 8, 2025
Total principal balance	$ 450
Minimum [Member] | Convertible Debt [Member] | Convertible Notes Dated February/March 2019 [Member]
Debt Instrument [Line Items]
Maturity Date	Feb. 28, 2024
Minimum [Member] | Convertible Debt [Member] | Convertible Note Dated June/July 2019 [Member]
Debt Instrument [Line Items]
Maturity Date	Jun. 7, 2024
Maximum [Member] | Convertible Debt [Member] | Convertible Notes Dated February/March 2019 [Member]
Debt Instrument [Line Items]
Maturity Date	Mar. 13, 2024
Maximum [Member] | Convertible Debt [Member] | Convertible Note Dated June/July 2019 [Member]
Debt Instrument [Line Items]
Maturity Date	Jul. 15, 2024

Long-Term Debt (Reconciliation

Long-Term Debt (Reconciliation Of Secured And Unsecured Contingent Obligation At Fair Value) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Secured Debt [Abstract]
Secured contingent payment obligation	$ 26,651
Secured contingent payment obligation	33,057	$ 26,651
Contingent Payment Obligation [Member] | Unsecured Debt [Member]
Secured Debt [Abstract]
Change in fair value	1,961
Unsecured Debt [Abstract]
Unsecured contingent payment obligation
Reclassification of other liabilities	1,003
Issuance of contingent payment rights	2,258
Change in fair value	1,961
Unsecured contingent payment obligation	5,222
Contingent Payment Obligation [Member] | Secured Debt [Member]
Secured Debt [Abstract]
Secured contingent payment obligation	26,651	25,557
Change in fair value	6,406	1,094
Secured contingent payment obligation	33,057	26,651
Unsecured Debt [Abstract]
Change in fair value	$ 6,406	$ 1,094

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details)	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets level 1 to Level 2 transfers	$ 0	$ 0
Assets level 2 to Level 1 transfers	0	0
Liabilities level 1 to Level 2 transfers	0	0
Liabilities level 2 to Level 1 transfers	0	$ 0
Fair value of note payable	$ 900,000
Measurement Input, Discount Rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | item	0.1415
Measurement Input, Risk Free Interest Rate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | item	0.0015
Measurement Input, Entity Credit Risk [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | item	0.08
Measurement Input, Litigation Inherent Risk [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input | item	0.06

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Secured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	$ 33,057	$ 26,651
Unsecured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	5,222
Quoted Prices In Active Markets (Level 1) [Member] | Secured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Quoted Prices In Active Markets (Level 1) [Member] | Unsecured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Significant Other Observable Inputs (Level 2) [Member] | Secured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Significant Other Observable Inputs (Level 2) [Member] | Unsecured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities
Significant Unobservable Inputs (Level 3) [Member] | Secured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	33,057	$ 26,651
Significant Unobservable Inputs (Level 3) [Member] | Unsecured Contingent Payment Obligation [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities	$ 5,222

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Information) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)item
Unsecured Debt [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 0
Duration	1 year
Unsecured Debt [Member] | Minimum [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.25
Unsecured Debt [Member] | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 7.3
Duration	2 years 6 months
Unsecured Debt [Member] | Weighted Average [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.25
Unsecured Debt [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 9.7
Duration	3 years 6 months
Unsecured Debt [Member] | Maximum [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.25
Secured Debt [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 0
Duration	1 year
Secured Debt [Member] | Minimum [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.05
Secured Debt [Member] | Weighted Average [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 46.1
Duration	2 years 6 months
Secured Debt [Member] | Weighted Average [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.23
Secured Debt [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated cash outflows | $	$ 70.2
Duration	3 years 6 months
Secured Debt [Member] | Maximum [Member] | Estimated Probabilities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Estimated probabilities | item	0.25

Income Taxes And Tax Status (Na

Income Taxes And Tax Status (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Tax Credit Carryforward [Line Items]
Foreign income tax expense
Current tax provision or benefit	$ 0	$ 0
Corporate tax rate	21.00%	21.00%
Operating loss carryforwards	$ 323,200,000
Operating loss carryforwards subject to expiration	294,100,000
Unrecognized tax benefits	927,000	$ 927,000	$ 927,000
Accrued interest or penalties	0	0
Income tax-related interest income, expense or penalties	0	$ 0
Research Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Tax credit carryforward, Amount	$ 6,600,000
Minimum [Member]
Tax Credit Carryforward [Line Items]
Operating loss carryforwards, expiration	Dec. 31, 2020
Period subject to IRS examination	2001
Minimum [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Operating loss carryforwards, expiration	Dec. 31, 2021
Maximum [Member]
Tax Credit Carryforward [Line Items]
Operating loss carryforwards, expiration	Dec. 31, 2037
Period subject to IRS examination	2020
Maximum [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward [Line Items]
Operating loss carryforwards, expiration	Dec. 31, 2038
Convertible Debt [Member] | Promissory Notes [Member]
Tax Credit Carryforward [Line Items]
Unrecognized tax benefits	$ 200,000

Income Taxes And Tax Status (Sc

Income Taxes And Tax Status (Schedule of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes And Tax Status [Abstract]
Tax benefit at statutory rate	$ (4,111)	$ (1,985)
State tax benefit	(842)	(407)
Increase in valuation allowance	4,307	2,341
Other	646	51
Income Tax Expense (Benefit), Total

Income Taxes And Tax Status (_2

Income Taxes And Tax Status (Schedule of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Taxes And Tax Status [Abstract]
Net operating loss carry-forward	$ 80,848	$ 83,865
Research and development credit carry-forward	6,603	7,608
Stock compensation	122	(28)
Patents and other	1,466	1,479
Contingent payment obligations	5,235	3,119
Inventories		139
Fixed assets	54	3
Accrued liabilities	64	200
Lease liabilities	77	142
Other		3
Deferred tax assets, gross	94,469	96,530
Less valuation allowance	(94,245)	(96,320)
Net deferred tax asset	224	210
Convertible debt	(224)	(210)
Deferred tax liabilities, gross	(224)	(210)
Net deferred tax asset

Income Taxes And Tax Status (_3

Income Taxes And Tax Status (Schedule of Unrecognized Tax Benefits Roll Forward) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Taxes And Tax Status [Abstract]
Unrecognized tax benefits, beginning of year	$ 927	$ 927
Unrecognized tax benefits, end of year	$ 927	$ 927

Commitments And Contingencies (

Commitments And Contingencies (Details) $ in Thousands	1 Months Ended									12 Months Ended
	Jul. 31, 2020item	Jun. 30, 2020item	May 31, 2020item	Apr. 30, 2020item	Feb. 29, 2020item	Jul. 31, 2019item	Mar. 31, 2018item	Mar. 31, 2017item	Dec. 31, 2015item	Dec. 31, 2020USD ($)item	Dec. 31, 2019USD ($)
Commitments and Contingencies [Line Items]
Accrued costs | $										$ 936	$ 1,081
Germany [Member]
Commitments and Contingencies [Line Items]
Statutory fees and costs | $										250	$ 370
Accrued costs | $										$ 140
ParkerVision v. Apple and Qualcomm (Middle District of Florida) [Member]
Commitments and Contingencies [Line Items]
Number of petitions						6
Number of patents allegedly infringed upon									4
Number of patents dismissed							3
Claim construction				7		2
ParkerVision v. Intel II (Western District of Texas) [Member]
Commitments and Contingencies [Line Items]
Number of patents allegedly infringed upon	2	1
Number of patents allegedly infringed upon			2		8					10
ParkerVision v. Qualcomm (Middle District of Florida) [Member]
Commitments and Contingencies [Line Items]
Number of petitions								6
Number of patents allegedly infringed upon										4
Number of patents found infringed upon								2
Number of patents found not infringed upon								3
Estimated loss | $										$ 1,300,000
Maximum [Member] | ParkerVision v. Apple and Qualcomm (Middle District of Florida) [Member]
Commitments and Contingencies [Line Items]
Claim construction				10

Stock Authorization And Issua_3

Stock Authorization And Issuance (Narratvie) (Details) - USD ($)	Jan. 25, 2021	Oct. 30, 2020	Jun. 08, 2020	Mar. 16, 2020	Feb. 10, 2020	Nov. 29, 2005	Mar. 31, 2021	Jan. 31, 2021	Mar. 31, 2020	Jan. 31, 2020	Dec. 31, 2020	Aug. 31, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Nov. 20, 2020	Jul. 31, 2020	Jun. 30, 2020	Feb. 28, 2020	Nov. 30, 2019	Oct. 31, 2019	Dec. 31, 2018	Nov. 17, 2005
Stock Authorization And Issuance [Line Items]
Preferred Stock, Shares authorized											15,000,000		15,000,000	15,000,000									100,000
Preferred Stock, Shares outstanding											0		0	0
Common stock, shares authorized											140,000,000		140,000,000	140,000,000	110,000,000		140,000,000	110,000,000		110,000,000	75,000,000
Exercise price per warrant											$ 0.45		$ 0.45	$ 0.45
Class of Warrant or Right, Weighted Average Remaining Life														3 years
Sale of common stock, number of shares												5,871,584
Sale of common stock														$ 4,766,000
Shares of common stock issued upon exercise of warrants														12,900,000	12,200,000
Estimated fair market value											$ 1,700,000		$ 1,700,000	$ 1,700,000	$ 1,300,000
Liquidated damages											1.00%
Maximum liquidated damages in the event in the even the common stock is not registered for resale within specific time periods											$ 100,000
Warrants, Options And Unvested RSUs [Member]
Stock Authorization And Issuance [Line Items]
Shares reserved for issuance											25,300,000		25,300,000	25,300,000
Aspire Capital [Member]
Stock Authorization And Issuance [Line Items]
Warrants Beneficially Own														9.99%
Warrants Beneficially Own, Prior Notice														61 days
Aspire Capital, Amendment [Member]
Stock Authorization And Issuance [Line Items]
Warrants to purchase common stock																			5,000,000
Exercise price per warrant											$ 0.001		$ 0.001	$ 0.001
Non-cash warrant expense														$ 1,780,000
warrants exercised														1,430,000
Proceeds from warrants exercised														$ 500,000
New Aspire Warrant [Member]
Stock Authorization And Issuance [Line Items]
Warrants to purchase common stock																			5,000,000
Exercise price per warrant																			$ 0.74
warrants exercised														3,070,000
Proceeds from warrants exercised														$ 1,100,000
Series E Preferred Stock [Member]
Stock Authorization And Issuance [Line Items]
Preferred Stock, Shares outstanding											0		0	0
Common Stock [Member]
Stock Authorization And Issuance [Line Items]
Sale of common stock														$ 148,000
Consultants [Member] | Chelsea Investor Relations [Member]
Stock Authorization And Issuance [Line Items]
Issuance of stock to consultants, shares					500,000
Issuance of stocks to consultants, value					$ 150,000
Agreement term														24 months
Consultants [Member] | Tailwinds Research Group LLC [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant				$ 1
Proceeds from warrants exercised				$ 60,000
Issuance of stock to consultants, shares				200,000
Shareholder Approved Equity Compensation Plans [Member]
Stock Authorization And Issuance [Line Items]
Shares reserved for issuance											200,000		200,000	200,000
Minimum [Member] | Aspire Capital, Amendment [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant																			0.35
Maximum [Member]
Stock Authorization And Issuance [Line Items]
Liquidated damages											6.00%
Maximum [Member] | Aspire Capital [Member]
Stock Authorization And Issuance [Line Items]
Warrants Beneficially Own														19.99%
Maximum [Member] | Aspire Capital, Amendment [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant																			$ 0.74
Subsequent Event [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant							$ 0.16
Third Party [Member]
Stock Authorization And Issuance [Line Items]
Sale of common stock, number of shares		70,000
Sale of common stock		$ 20,000
Third Party [Member] | Subsequent Event [Member]
Stock Authorization And Issuance [Line Items]
Sale of common stock								$ 30,000
Principal [Member] | Convertible Debt [Member]
Stock Authorization And Issuance [Line Items]
Shares reserved for issuance											23,600,000		23,600,000	23,600,000
Interest In-Kind [Member] | Convertible Debt [Member]
Stock Authorization And Issuance [Line Items]
Shares reserved for issuance											7,500,000		7,500,000	7,500,000
Rights Agreement [Member]
Stock Authorization And Issuance [Line Items]
Redemption price											$ 0.01		$ 0.01	$ 0.01
Exercise price per warrant						$ 8.54
Threshold percentage at which rights separte from common stock						15.00%
Rights Agreement [Member] | Minimum [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant																$ 14.50
Rights Agreement [Member] | Maximum [Member]
Stock Authorization And Issuance [Line Items]
Exercise price per warrant																$ 8.54
Private Placements With Accredited Investors [Member]
Stock Authorization And Issuance [Line Items]
Proceeds from issurance of common stock									$ 900,000	$ 200,000			$ 3,800,000
Aggregate offering price									$ 0.35		$ 0.35		$ 0.35	$ 0.35
Aggregate offering shares									2,571,432		10,857,876		10,857,876	10,857,876
Unsecured promissory note									$ 900,000		$ 1,800,000		$ 1,800,000	$ 1,800,000
Private Placements With Accredited Investors [Member] | Subsequent Event [Member]
Stock Authorization And Issuance [Line Items]
Proceeds from issurance of common stock							$ 4,200,000	1,000,000
Aggregate offering price								$ 0.35
Aggregate offering shares							3,230,942	2,976,430
Warrants to purchase common stock							1,619,289
Exercise price per warrant							$ 1.75
Liquidated damages							1.00%	1.00%
Maximum liquidated damages in the event in the even the common stock is not registered for resale within specific time periods							$ 250,000	$ 60,000
Private Placements With Accredited Investors [Member] | Subsequent Event [Member] | Maximum [Member]
Stock Authorization And Issuance [Line Items]
Liquidated damages							6.00%	6.00%
Private Placements With Accredited Investors B [Member]
Stock Authorization And Issuance [Line Items]
Aggregate offering price										$ 0.13
Aggregate offering shares										1,169,232
Private Placements With Accredited Investors C [Member]
Stock Authorization And Issuance [Line Items]
Aggregate offering price										$ 0.15
Aggregate offering shares										166,667
Chelsea Investor Relations [Member] | Subsequent Event [Member]
Stock Authorization And Issuance [Line Items]
Issuance of stock to consultants, shares	500,000
Issuance of stocks to consultants, value	$ 330,000
Securities Purchase Agreements [Member] | Third Party [Member]
Stock Authorization And Issuance [Line Items]
Shelf, authorized shares														50,000
Sale of common stock, number of shares			30,000											100,000
Sale of common stock			$ 10,000											$ 50,000
Securities Purchase Agreements [Member] | Third Party [Member] | Subsequent Event [Member]
Stock Authorization And Issuance [Line Items]
Sale of common stock, number of shares								50,000
Contingent Payment Obligation [Member] | Unsecured Debt [Member]
Stock Authorization And Issuance [Line Items]
Unsecured promissory note											5,222,000		5,222,000	5,222,000
Contingent Payment Rights [Member] | Unsecured Debt [Member]
Stock Authorization And Issuance [Line Items]
Fair value of payment obligation											$ 2,500,000		$ 2,500,000	$ 2,500,000
Contingent Payment Rights [Member] | Third Party [Member] | Unsecured Debt [Member]
Stock Authorization And Issuance [Line Items]
Unsecured promissory note		20,000
Fair value of payment obligation		$ 100,000

Stock Authorization And Issua_4

Stock Authorization And Issuance (Summary Of Equity Offerings) (Details)	12 Months Ended
	Dec. 31, 2020USD ($)$ / sharesshares
Equity Offerings [Line Items]
# of Common Shares/ Units Sold	$ 4,766,000
Average Exercise Price Per Warrant | $ / shares	$ 0.45
Common Stock [Member]
Equity Offerings [Line Items]
# of Common Shares/ Units Sold	$ 148,000
Common Stock [Member] | Private Placement Of Common Stock [Member] | January 2020 [Member]
Equity Offerings [Line Items]
# of Common Shares/ Units Sold	$ 1,335
Average Price per Share/Unit | $ / shares	$ 0.13
Net Proceeds	$ 177,000
Common Stock [Member] | Private Placement Of Common Stock, Amended To Add CPR [Member] | March 2020 [Member]
Equity Offerings [Line Items]
# of Common Shares/ Units Sold	$ 2,571
Average Price per Share/Unit | $ / shares	$ 0.35
Net Proceeds	$ 900,000
Common Stock [Member] | Private Placement Of Common Stock With CPRs [Member] | April 2020 to December 2020 [Member]
Equity Offerings [Line Items]
# of Common Shares/ Units Sold	$ 10,858
Average Price per Share/Unit | $ / shares	$ 0.35
Net Proceeds	$ 3,724,000
Warrants Outstanding [Member] | Warrant Amendment [Member] | February 2020 [Member]
Equity Offerings [Line Items]
Number of warrants issued | shares	5,000,000
Average Exercise Price Per Warrant | $ / shares	$ 0.74

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, net of estimated forfeitures	$ 360,000
Expected weighted average period to recognize the compensation cost, in years	6 months
2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	20,473
Maximum number of shares per employee	5,000
Number of shares authorized	50,000
2011 Long Term Incentive Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	25,627
Maximum number of shares per employee	150,000
Number of shares authorized	3,000,000
2019 Long-Term Incentive Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	155,000
Number of shares authorized	12,000,000		12,000,000
Restricted Stock Award And Restricted Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested fair value	$ 300,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of option shares granted	$ 0.27	$ 0.14
Fair market value of vested shares	$ 900,000	$ 500,000
Intrinsic value of options exercised	$ 0	$ 0
Minimum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Maximum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Non Employee Directors [Member] | Maximum [Member] | 2019 Long-Term Incentive Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee	1,000,000
Weighted average fair value of option shares granted	$ 175,000
Non Employee [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year

Share-Based Compensation (Sched

Share-Based Compensation (Schedule Of Share-Based Compensation Expense Included In Statements Of Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 1,244	$ 589
Research And Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense		5
Selling, General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 1,244	$ 584

Share-Based Compensation (Summa

Share-Based Compensation (Summary Of Restricted Stock Activity) (Details) - Restricted Stock Award And Restricted Stock Unit [Member] shares in Thousands	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested at beginning of year, Shares | shares
Granted, Shares | shares	1,016
Vested, Shares | shares	(829)
Non-vested at end of year, Shares | shares	187
Non-vested at beginning of year, Weighted-Average Grant-Date Fair Value | $ / shares
Granted, Weighted Average Grant Date Fair Value | $ / shares	0.31
Vested, Weighted Average Grant Date Fair Value | $ / shares	0.31
Non-vested at end of year, Weighted-Average Grant-Date Fair Value | $ / shares	$ 0.33

Share-Based Compensation (Sum_2

Share-Based Compensation (Summary Of Option Activity) (Details) - Stock Options [Member] $ / shares in Units, shares in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Shares, Beginning of year | shares	11,410
Granted, Shares | shares	843
Exercised, Shares | shares
Forfeited, Shares | shares	(13)
Outstanding, Shares, End of year | shares	12,240
Outstanding, Weighted Average Exercise Price, Beginning of year | $ / shares	$ 0.33
Granted, Weighted Average Exercise Price | $ / shares	0.31
Exercised, Weighted Average Exercise Price | $ / shares
Forfeited, Weighted Average Exercise Price | $ / shares	38.86
Outstanding, Weighted Average Exercise Price, End of year | $ / shares	$ 0.28
Outstanding, Weighted Average Remaining Contractual Term	5 years 6 months
Outstanding, Aggregate Intrinsic Value | $	$ 3,401
Vested and expected to vest at end of year, shares | shares	9,490
Vested and expected to vest at end of year, weighted average exercise price | $ / shares	$ 0.31
Vested and expected to vest at end of year, weighted average remaining contractual term	5 years 6 months
Vested and expected to vest at end of year, aggregate intrinsic value | $	$ 2,578

Share-Based Compensation (Sum_3

Share-Based Compensation (Summary Of Valuation Assumptions) (Details) - Stock Options [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected option term	5 years	5 years
Expected annual dividend yield	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility factor	127.40%	119.10%
Risk-free interest rate	0.33%	1.60%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility factor	135.30%
Risk-free interest rate	1.63%

Share-Based Compensation (Sum_4

Share-Based Compensation (Summary Of Options And Warrants By Exercise Price Range) (Details) - Stock Options [Member] shares in Thousands	12 Months Ended
	Dec. 31, 2020$ / sharesshares
Options Outstanding
Number Outstanding | shares	12,240
Wtd. Avg. Exercise Price	$ 0.28
Wtd. Avg. Remaining Contractual Life	5 years 6 months
Options Vested
Number Exercisable | shares	9,490
Wtd. Avg. Exercise Price	$ 0.31
Wtd. Avg. Remaining Contractual Life	5 years 6 months
$0.171 - $0.33 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Excercise price minimum	$ 0.171
Exercise price maximum	$ 0.33
Options Outstanding
Number Outstanding | shares	11,318
Wtd. Avg. Exercise Price	$ 0.18
Wtd. Avg. Remaining Contractual Life	5 years 7 months 6 days
Options Vested
Number Exercisable | shares	8,624
Wtd. Avg. Exercise Price	$ 0.18
Wtd. Avg. Remaining Contractual Life	5 years 7 months 6 days
$0.50 - $0.60 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Excercise price minimum	$ 0.50
Exercise price maximum	$ 0.60
Options Outstanding
Number Outstanding | shares	513
Wtd. Avg. Exercise Price	$ 0.59
Wtd. Avg. Remaining Contractual Life	5 years
Options Vested
Number Exercisable | shares	457
Wtd. Avg. Exercise Price	$ 0.60
Wtd. Avg. Remaining Contractual Life	4 years 9 months 18 days
$1.98 - $2.13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Excercise price minimum	$ 1.98
Exercise price maximum	$ 2.13
Options Outstanding
Number Outstanding | shares	381
Wtd. Avg. Exercise Price	$ 2.02
Wtd. Avg. Remaining Contractual Life	3 years 4 months 24 days
Options Vested
Number Exercisable | shares	381
Wtd. Avg. Exercise Price	$ 2.02
Wtd. Avg. Remaining Contractual Life	3 years 4 months 24 days
$13.80 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price maximum	$ 13.80
Options Outstanding
Number Outstanding | shares	28
Wtd. Avg. Exercise Price	$ 13.80
Wtd. Avg. Remaining Contractual Life	6 months
Options Vested
Number Exercisable | shares	28
Wtd. Avg. Exercise Price	$ 13.80
Wtd. Avg. Remaining Contractual Life	6 months

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 31, 2020
Related Party Transaction [Line Items]
Common stock, shares issued	58,591,000	34,097,000
Sterne, Kessler, Goldstein & Fox, PLLC [Member]
Related Party Transaction [Line Items]
Amount paid to related party	$ 10,000	$ 20,000
Stacie Wilf [Member]
Related Party Transaction [Line Items]
Accounts payable			$ 80,000
Common stock, shares issued			500,000
Promissory Notes [Member] | Unsecured Debt [Member] | Sterne, Kessler, Goldstein & Fox, PLLC [Member]
Related Party Transaction [Line Items]
Amount paid to related party	100,000	$ 0
Secured notes payable	$ 800,000

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)

Mar. 26, 2021

Mar. 09, 2021

Jan. 25, 2021

Jan. 11, 2021

Mar. 31, 2021

Jan. 31, 2021

Mar. 31, 2020

Jan. 31, 2020

Mar. 31, 2021

Dec. 31, 2020

Dec. 31, 2020

Dec. 31, 2019

Aug. 31, 2019

Subsequent Event [Line Items]

Amount received from investors

$ 400,000

$ 400,000

Liquidated damages

1.00%

Maximum liquidated damages in the event in the even the common stock is not registered for resale within specific time periods

$ 100,000

Exercise price per warrant

$ 0.45

$ 0.45

Subsequent Event [Member]

Subsequent Event [Line Items]

Exercise price per warrant

$ 0.16

$ 0.16

Payment to settle outstanding accounts and notes payable for litigation costs

$ 3,000,000

Private Placements With Accredited Investors [Member]

Subsequent Event [Line Items]

Aggregate offering shares

2,571,432

10,857,876

10,857,876

Aggregate offering price

$ 0.35

$ 0.35

$ 0.35

Proceeds from issurance of common stock

$ 900,000

$ 200,000

$ 3,800,000

Private Placements With Accredited Investors [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Aggregate offering shares

3,230,942

2,976,430

3,230,942

Aggregate offering price

$ 0.35

Proceeds from issurance of common stock

$ 4,200,000

$ 1,000,000

Liquidated damages

1.00%

1.00%

Maximum liquidated damages in the event in the even the common stock is not registered for resale within specific time periods

$ 250,000

$ 60,000

Warrants to purchase common stock

1,619,289

1,619,289

Exercise price per warrant

$ 1.75

$ 1.75

Commitment to file registration statement, period

30 days

Commitment to file, effective period

90 days

Chelsea Investor Relations [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Issuance of stock to consultants, shares

500,000

Issuance of stocks to consultants, value

$ 330,000

2019 Long-Term Incentive Equity Plan [Member]

Subsequent Event [Line Items]

Number of shares authorized

12,000,000

12,000,000

12,000,000

2019 Long-Term Incentive Equity Plan [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Number of shares authorized

27,000,000

Exercise price

$ 0.54

Option period

2 years

2019 Long-Term Incentive Equity Plan [Member] | Jeffrey Parker [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Maximum number of shares per employee

8,000,000

2019 Long-Term Incentive Equity Plan [Member] | Cynthia French [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Maximum number of shares per employee

1,000,000

2019 Long-Term Incentive Equity Plan [Member] | Three Non-Employee Directors [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Maximum number of shares per employee

380,000

2019 Long-Term Incentive Equity Plan [Member] | Other Key Employees [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Maximum number of shares per employee

2,900,000

2019 Long-Term Incentive Equity Plan [Member] | Consultants [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Shares granted

32,000

Agreement term

1 year

Share granted, value

$ 50,000

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. [Member]

Subsequent Event [Line Items]

Estimated loss

$ 3,600,000

$ 3,600,000

$ 3,600,000

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Payment to settle outstanding accounts and notes payable for litigation costs

$ 3,000,000

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. [Member] | Note Payable To A Related Party [Member] | Secured Debt [Member]

Subsequent Event [Line Items]

Long-term note payable, related party

3,100,000

3,100,000

Accrued interest

$ 30,000

$ 30,000

Maximum [Member]

Subsequent Event [Line Items]

Liquidated damages

6.00%

Maximum [Member] | Private Placements With Accredited Investors [Member] | Subsequent Event [Member]

Subsequent Event [Line Items]

Liquidated damages

6.00%

6.00%