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Income Taxes (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Income Taxes [Line Items] |  |
Valuation allowance | $ 11,476,000 | $ 12,067,000
Provision or benefit for income taxes | (17,000) | (242,000)
Federal net operating loss carryforwards | 35,600,000 |
Deferred tax asset | $ 130,000 | $ 242,000
Federal tax rate | 21.00% | 34.00%
Refundable credits | $ 260,000 |
Decrease in deferred tax asset | 5,300,000 |
Accounts receivable - noncurrent | 130,000 | $ 242,000
Tax Period Between 2019 And 2037 [Member] |  |
Income Taxes [Line Items] |  |
Federal net operating loss carryforwards | 34,600,000 |
Indefinite Tax Period [Member] |  |
Income Taxes [Line Items] |  |
Federal net operating loss carryforwards | $ 1,000,000 |
Accounting Standards Update 2016-09 [Member] |  |
Income Taxes [Line Items] |  |
Increase to retained earnings |  | $ 687,000
Minimum [Member] | Tax Period Between 2019 And 2037 [Member] |  |
Income Taxes [Line Items] |  |
Federal net operating loss carryforwards expiration between, years | Jan. 01, 2019 |
Maximum [Member] | Tax Period Between 2019 And 2037 [Member] |  |
Income Taxes [Line Items] |  |
Federal net operating loss carryforwards expiration between, years | Dec. 31, 2037 |

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- Definition Amount due from customers or clients, more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(5)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(17)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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