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Revenue Concentration (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
Revenue Concentration (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Revenue, Major Customer [Line Items]
Revenue	$ 22,067	$ 17,683
Accounts receivable, net	12,875		$ 14,938
Customer Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Revenue	8,100	5,500
Customer Concentration Risk \| Accounts Receivable
Revenue, Major Customer [Line Items]
Accounts receivable, net	$ 4,400	$ 3,900
Customer Concentration Risk \| Customer One \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	20.00%	20.00%
Customer Concentration Risk \| Customer Two \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	17.00%	11.00%
Geographic Concentration Risk \| Sales Revenue Net
Revenue, Major Customer [Line Items]
Total revenue, percentage	25.00%	35.00%
Geographic Concentration Risk \| Long-term Assets \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage	62.00%		68.00%
Geographic Concentration Risk \| Long-term Assets, Excluding Goodwill and Intangibles \| International
Revenue, Major Customer [Line Items]
Total revenue, percentage	15.00%		12.00%