Segment Information - Major customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Segment Reporting Information [Line Items]
Customer Revenues	$ 16,095	$ 16,350	$ 32,667	$ 35,330
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	$ 500	$ 1,700	$ 3,100	$ 3,000
% of Total Revenues	3.00%	11.00%	10.00%	9.00%
Customer B | Sales Revenue, Net [Member] | Customer Concentration Risk
Segment Reporting Information [Line Items]
Customer Revenues	$ 2,000	$ 1,000	$ 3,800	$ 2,000
% of Total Revenues	13.00%	6.00%	12.00%	6.00%
Customer B | Accounts Receivable | Customer Concentration Risk
Segment Reporting Information [Line Items]
Accounts receivable, gross	$ 5,600		$ 5,600		$ 7,400
% of Total Revenues			31.00%		36.00%