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Segment Information - Major customers (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Segment Reporting Information [Line Items]
Customer Revenues	$ 11,388	$ 16,858
Accounts Receivable \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk percentage	10.00%
Customer A \| Sales Revenue, Net \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Customer Revenues	$ 1,140	$ 330
Concentration risk percentage	10.00%	2.00%
Customer B \| Sales Revenue, Net
Segment Reporting Information [Line Items]
Customer Revenues	$ 611	$ 1,784
Concentration risk percentage	5.00%	11.00%
Customer B \| Accounts Receivable \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Accounts receivable, gross	$ 4,800		$ 4,700
Concentration risk percentage	30.00%		28.00%
Customer C \| Sales Revenue, Net \| Customer Concentration Risk
Segment Reporting Information [Line Items]
Customer Revenues	$ 333	$ 2,630
Concentration risk percentage	3.00%	16.00%