Supplemental Guarantor Information - Condensed Consolidating Statements of Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	$ 184.7	$ 146.4	$ 340.7	$ 290.8
Consolidating Adjustments
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	(427.2)	(342.3)	(789.7)	(678.9)
Parent Guarantor | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	184.7	146.4	340.7	290.8
Subsidiary Issuer | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	184.8	146.5	340.9	291.0
Guarantor Subsidiaries | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	231.8	207.9	409.4	372.8
Non-Guarantor Subsidiaries | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	10.6	(12.1)	39.4	15.1
Affiliated Entity | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Comprehensive income (loss)	$ 0.0	$ 0.0	$ 0.0	$ 0.0