Goodwill and Intangibles (Tables)

3 Months Ended

Mar. 31, 2018

Goodwill [Line Items]

Schedule of Goodwill [Table Text Block]

	As of March 31,
	2018		2017
Net carrying value at beginning of period	$	444.7	$	212.8
Addition to goodwill from acquisition	—		—
Measurement period adjustment to previously recorded goodwill	0.9		—
Net carrying value at end of period	$	445.6	$	212.8

Schedule of Finite-Lived Intangible Assets

	Three Months Ended March 31,
	2018			2017
CDI, net, beginning of period	$	49.1		$	9.7
CDI current period amortization	(1.8		)	(0.6		)
Total CDI, net, end of period	$	47.3		$	9.1

Schedule of Future Amortization Expense

The following table provides the estimated future CDI amortization expense:

Years Ending December 31,
2018 remaining	$	5.2
2019	6.6
2020	6.2
2021	5.7
2022	5.3
Thereafter	18.3
Total	$	47.3