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Summary of Significant Accounting Policies (Intangibles) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Intangible Assets [Line Items] |  |
Impairment of goodwill | $ 0 | $ 0
Intangibles, net of accumulated amortization | 1,526,000 | 1,651,000
Amortization expense | 125,000 |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |  |
2018 | 125,000 |
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 | 1,633,000 | 1,508,000
Net Book Value | 1,526,000 | 1,651,000
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 | 20 years
Intangible assets, weighted average remaining life | 7 years |
Finite-Lived Intangible Assets, Net [Abstract] |  |
Gross Carrying Value | $ 2,505,000 | $ 2,505,000
Accumulated Amortization | 1,633,000 | 1,508,000
Net Book Value | $ 872,000 | $ 997,000

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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