Segment Information - Major customers (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Segment Reporting Information [Line Items]
Customer Revenues	$ 16,572	$ 18,980
Accounts Receivable | Customer Concentration Risk
Segment Reporting Information [Line Items]
% of Total Revenues	10.00%
Customer A | Sales Revenue, Net [Member] | Customer Concentration Risk
Segment Reporting Information [Line Items]
Customer Revenues	$ 2,600	$ 1,300
% of Total Revenues	16.00%	7.00%
Customer B
Segment Reporting Information [Line Items]
Customer Revenues	$ 1,800	$ 1,000
% of Total Revenues	11.00%	5.00%
Customer B | Accounts Receivable | Customer Concentration Risk
Segment Reporting Information [Line Items]
Accounts receivable, gross	$ 5,600		$ 7,400
% of Total Revenues	32.00%		36.00%