Major Customers and Foreign Sales (Details) - Net Revenues	6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Customer Concentration Risk | Customer One
Revenue, Major Customer [Line Items]
Concentration risk, percentage	11.00%	14.00%
Geographic Concentration Risk
Revenue, Major Customer [Line Items]
Concentration risk, percentage	100.00%	100.00%
Geographic Concentration Risk | United States
Revenue, Major Customer [Line Items]
Concentration risk, percentage	40.00%	21.00%
Geographic Concentration Risk | Other North America
Revenue, Major Customer [Line Items]
Concentration risk, percentage	2.00%	3.00%
Geographic Concentration Risk | Total North America
Revenue, Major Customer [Line Items]
Concentration risk, percentage	42.00%	24.00%
Geographic Concentration Risk | China
Revenue, Major Customer [Line Items]
Concentration risk, percentage	19.00%	28.00%
Geographic Concentration Risk | Malaysia
Revenue, Major Customer [Line Items]
Concentration risk, percentage	3.00%	5.00%
Geographic Concentration Risk | Taiwan
Revenue, Major Customer [Line Items]
Concentration risk, percentage	6.00%	9.00%
Geographic Concentration Risk | Other Asia
Revenue, Major Customer [Line Items]
Concentration risk, percentage	7.00%	5.00%
Geographic Concentration Risk | Total Asia
Revenue, Major Customer [Line Items]
Concentration risk, percentage	35.00%	47.00%
Geographic Concentration Risk | Germany
Revenue, Major Customer [Line Items]
Concentration risk, percentage	11.00%	14.00%
Geographic Concentration Risk | Other Europe
Revenue, Major Customer [Line Items]
Concentration risk, percentage	12.00%	15.00%
Geographic Concentration Risk | Total Europe
Revenue, Major Customer [Line Items]
Concentration risk, percentage	23.00%	29.00%