Goodwill and Intangibles (Tables)

9 Months Ended

Sep. 30, 2018

Goodwill [Line Items]

Schedule of Goodwill [Table Text Block]

	As of September 30,
	2018		2017
Net carrying value at beginning of nine month period	$	444.7	$	212.8
Addition to provisional goodwill from acquisition	100.8		232.2
Measurement period adjustment to previously recorded goodwill	0.9		—
Net carrying value at end of period	$	546.4	$	445.0

Schedule of Finite-Lived Intangible Assets

	Three Months Ended September 30,						Nine Months Ended September 30,
	2018			2017			2018			2017
CDI, net, beginning of period	$	45.6		$	52.8		$	49.1		$	9.6
Established through acquisitions or provisional adjustments	15.7			—			15.7			48.0
Reductions due to sale of accounts	—			—			—			(3.1		)
CDI current period amortization	(2.0		)	(1.9		)	(5.5		)	(3.6		)
Total CDI, net, end of period	$	59.3		$	50.9		$	59.3		$	50.9

Schedule of Future Amortization Expense

The following table provides the estimated future CDI amortization expense:

Years Ending December 31,
2018 remaining	$	2.4
2019	8.9
2020	8.1
2021	7.5
2022	6.9
Thereafter	25.5
Total	$	59.3