Commitments and Contingencies (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2019	Sep. 30, 2018
Schedule of Equity Method Investments [Line Items]
Purchase obligation	$ 6.0	$ 7.3
Minimum
Schedule of Equity Method Investments [Line Items]
Severance payment term	12 months
Maximum
Schedule of Equity Method Investments [Line Items]
Severance payment term	36 months