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Concentrations of Credit Risk and Major Customers (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 Customer | Dec. 31, 2019 USD ($) Customer | Dec. 31, 2018
Concentration Risk |  |  |
Concentration of risk, number of customers | 5 |  |
Concentration Risk, Percentage | 34.00% | 36.00% | 37.00%
Sales Revenue and Services, Net [Member] | Customer Concentration Risk [Member] |  |  |
Concentration Risk |  |  |
Concentration of risk, number of customers | 0 | 1 |
Concentration Risk, Percentage |  | 10.90% | 12.50%
Baseline percentage for customer concentration of risk | 10.00% | 10.00% |
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |  |
Concentration Risk |  |  |
Accounts receivable | $ |  | $ 5.8 |
Concentration Risk, Percentage | 30.00% | 30.00% |

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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -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=119400593&loc=d3e572229-122910 + Details
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