Leases (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Sep. 30, 2018
Leases [Abstract]
Operating lease costs	$ 0.6	$ 2.1	$ 1.6
Short-term lease costs		0.9
Variable lease costs		0.7
Total	$ 0.6	$ 3.7	$ 1.6
Weighted average remaining lease term		22 months 12 days
Weighted average discount rate		8.30%