Condensed Consolidated Statement of Comprehensive Income - USD ($)	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Condensed Consolidated Statement of Other Comprehensive Income (Loss) [Abstract]
Net income	$ 18.2	$ (6.9)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment		(2.2)
Reclassification of adjustments included in net income [Abstract]
Other comprehensive income (loss)	0.3	(2.2)
Comprehensive income	$ 18.5	$ (9.1)