Central Merger and Restructuring, Merger and Integration Costs - Schedule of Acquisition Related Costs (Details) - Central Merger - USD ($) $ in Millions		12 Months Ended
Sep. 27, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Acquisition related costs	$ 0.8	$ 1.2	$ 6.9	$ 7.2
General and administrative expenses
Business Acquisition [Line Items]
Acquisition related costs		1.2	4.5	6.2
Depreciation and amortization
Business Acquisition [Line Items]
Acquisition related costs		$ 0.0	$ 2.4	$ 1.0

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration