Consolidated Statements of Operations - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net service revenues	$ 1,713.6	$ 2,404.6	$ 2,353.6
Cost of services provided	1,259.8	1,766.4	1,727.5
Gross profit	453.8	638.2	626.1
Selling, general and administrative expense	311.8	452.2	481.2
Amortization expense	92.9	56.3	104.9
Income from operations	49.1	129.7	40.0
Other income (expense)	1.4		(23.5)
Interest expense	73.7	72.5	97.8
Income (loss) before income taxes	(23.2)	57.2	(81.3)
Income tax (expense) benefit	9.2	(12.8)	66.2
Net income (loss)	$ (14.0)	$ 44.4	$ (15.1)
Income (loss) per share:
Basic and Diluted	$ (0.18)	$ 0.43	$ (0.18)