Intangible Assets, net (Tables)

3 Months Ended

Mar. 31, 2017

Intangible Assets, net

Summary of intangible assets, net

		March 31, 2017				December 31, 2016
	Weighted Average	Gross				Gross
	Amortizable	Carrying		Accumulated		Carrying		Accumulated
	Life in Years	Amount		Amortization		Amount		Amortization
		(in millions)
Intangible assets subject to amortization:
Covenants not to compete	4.8	$	1.1	$	(0.7)	$	1.1	$	(0.6)
Customer lists/relationships	14.6		737.3		(352.3)		736.7		(338.9)
Software	10.0		8.1		(8.1)		8.1		(8.1)
Other	5.2		6.3		(5.6)		6.3		(5.5)
			752.8		(366.7)		752.2		(353.1)
Intangible assets not subject to amortization:
Trade names			752.4		—		752.2		—
		$	1,505.2	$	(366.7)	$	1,504.4	$	(353.1)

Summary of estimated aggregate amortization expense

The following is a summary of estimated aggregate amortization expense for the remaining nine months of 2017 and each of the succeeding five years:

	(in millions)
2017 (remaining nine months)	$	37.0
2018		46.0
2019		45.9
2020		45.9
2021		42.0
2022		33.9