Warrants (Tables)
 12 Months Ended
Dec. 31, 2021
Warrants [Abstract]  
Summary of Warrants Issued and Warrants Outstanding Issued Outstanding Exercise Price Expiration2016 Warrant Issuance 2,947,949 1,680,447 2.60 Feb 20222017 Warrant Issuance (1) 100,000 100,000 2.25 Mar 20222017 Warrant Issuance (2) 1,650,000 1,650,000 2.45 Nov 20222018 Warrant Issuance (2) 4,004,329 2,909,374 1.55 Jul 20232019 Warrant Issuance (3) 6,000,000 3,000,000 0.78 Oct 2024 9,339,821 (1)Issued in conjunction with an unsecured line of credit.(2)Warrants are subject to liability accounting.(3)Private Placement unregistered warrants exercisable six months following issuance.
Fair Value of Warrants December 31 December 31, 2021 20202018 January and February Issuance Fair Value $ 1,355 $ 3,577 2017 May Issuance Fair Value 19 1,045 $ 1,374 $ 4,622 Twelve Months Ended December 31 2021 2020Change in Fair Value of common stock warrant liability (1) 3,248 (4,599) (1)The combined changes in fair value is reflected as income from change in the fair market value of common stock warrant liability.