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Summary of Significant Accounting Policies (Intangibles) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Intangible Assets [Line Items] |  |  |
Impairment of goodwill | $ 0 | $ 0 |
Intangibles, net of accumulated amortization | 1,401,000 | 1,526,000 |
Amortization expense | 125,000 | 125,000 | $ 125,000
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |  |  |
2019 | 125,000 |  |
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 | 1,758,000 | 1,633,000 |
Net Book Value | 1,401,000 | 1,526,000 |
Impairment of intangible assets | 0 | 0 |
Trade Name |  |  |
Intangible Assets [Line Items] |  |  |
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 |  |  |
Intangible Assets [Line Items] |  |  |
Intangible assets, useful life | 20 years |  |
Intangible assets, weighted average remaining life | 6 years |  |
Finite-Lived Intangible Assets, Net [Abstract] |  |  |
Gross Carrying Value | $ 2,505,000 | 2,505,000 |
Accumulated Amortization | 1,758,000 | 1,633,000 |
Net Book Value | $ 747,000 | $ 872,000 |

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