Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Product lines | Combined sales
Related Party Transaction [Line Items]
Concentration risk, percentage	12.00%	11.00%
Air Products
Related Party Transaction [Line Items]
Total Allocated Costs	$ 21.3	$ 26.3	$ 26.0
Daido Air Products Electronics, Inc. | Product lines | Combined sales
Related Party Transaction [Line Items]
Concentration risk, percentage		2.00%	2.00%
Cost of sales | Air Products
Related Party Transaction [Line Items]
Total Allocated Costs	2.8	$ 3.6	$ 4.6
Selling and administrative | Air Products
Related Party Transaction [Line Items]
Total Allocated Costs	16.8	17.8	19.3
Research and development | Air Products
Related Party Transaction [Line Items]
Total Allocated Costs	1.0	1.4	1.9
Business restructuring and cost reduction actions | Air Products
Related Party Transaction [Line Items]
Total Allocated Costs	$ 0.7	$ 3.5	$ 0.2