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Summary of Significant Accounting Policies (Contract Balances) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Accounts receivable - contracts with customers	$ 4,353	$ 5,454
Accounts receivable - non-ASC 606	3,157	3,649
Total Accounts Receivable	7,510	9,103
Less: Allowance for doubtful accounts	(291)	(569)
Total Accounts Receivable, net	7,219	8,534
Deferred income	81	185
Revenue recognized	$ 176	$ 1,900

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Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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