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Summary of Significant Accounting Policies (Contract Balances) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Accounting Policies [Abstract] |  |
Accounts receivable - contracts with customers | $ 3,061 | $ 2,390
Accounts receivable - ASC 842 | 6,963 | 5,120
Total Accounts Receivable | 10,024 | 7,510
Less: Allowance for doubtful accounts | (918) | (291)
Total Accounts Receivable, net | 9,106 | 7,219
Deferred income | $ 640 | $ 81

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