Acquisition (Tables)

12 Months Ended

Dec. 31, 2017

Dec. 31, 2016

Acquisitions [Abstract]

Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]

The fair value and weighted average useful lives that have been assigned to the acquired identifiable intangible assets of this acquisition are:

(in millions, except useful life)	Fair Value		Weighted Average Useful Life
Customer relationships	$	0.5	5 years

The fair value and weighted average useful lives that have been assigned to the acquired identifiable intangible assets of this acquisition are:

(in millions, except useful life)	Fair Value		Weighted Average Useful Life
Customer relationships	$	21.8	8 years
Order backlog	1.7		2 months
Total	$	23.5

The fair value and weighted average useful life that has been assigned to the acquired identifiable intangible asset of this acquisition is:

(in millions, except useful life)	Fair Value		Weighted Average Useful Life
Customer relationships	$	4.5	10 years