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Intangibles (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Intangible Assets [Line Items] |  |  |
Intangibles, net of accumulated amortization | $ 1,276,000 | $ 1,401,000 |
Amortization expense | 125,000 | 125,000 | $ 125,000
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |  |  |
2020 | 125,000 |  |
2021 | 125,000 |  |
2022 | 125,000 |  |
2023 | 125,000 |  |
2024 | 125,000 |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |  |
Gross Carrying Value | 3,159,000 | 3,159,000 |
Accumulated Amortization | 1,883,000 | 1,758,000 |
Net Book Value | 1,276,000 | 1,401,000 |
Impairment of intangible assets | 0 | 0 |
Trade Name |  |  |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |  |  |
Indefinite-lived intangible asset, gross carrying value | 654,000 |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |  |
Gross Carrying Value | 654,000 | 654,000 |
Accumulated Amortization | 0 | 0 |
Net Book Value | $ 654,000 | 654,000 |
Developed Technology |  |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |  |
Intangible assets, useful life | 20 years |  |
Gross Carrying Value | $ 2,505,000 | 2,505,000 |
Accumulated Amortization | 1,883,000 | 1,758,000 |
Net Book Value | $ 622,000 | $ 747,000 |

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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