Intangible Assets - Schedule of intangible assets (Detail) - USD ($) $ in Thousands |
Jun. 30, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|---|
| Finite-Lived Intangible Assets, Gross | $ 1,071 | $ 994 | |
| Less: Accumulated amortization | (320) | (239) | |
| Intangible assets, net | $ 706 | 751 | 755 |
| Patents [Member] | |||
| Finite-Lived Intangible Assets, Gross | 591 | 547 | |
| FCC Licenses [Member] | |||
| Finite-Lived Intangible Assets, Gross | $ 480 | $ 447 |
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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