Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allocation of costs
Direct labor expenses	$ 1.2	$ 1.0	$ 2.4	$ 1.8
General and administrative expense	$ 13.8	$ 12.4	$ 26.8	$ 23.9

Payroll costs incurred (including equity-based compensation) that are directly related to services rendered by an entity during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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