Incentive Plan - Schedule of Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Long-term incentive units
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	$ 2.8	$ 3.1	$ 6.0	$ 6.2
Deferred compensation, capitalized			0.1	0.1
Unearned Compensation	24.9		$ 24.9		$ 15.1
Expected period to recognize unearned compensation (in years)			2 years 3 months 18 days
Market performance-based awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	6.4	6.6	$ 14.9	11.2
Deferred compensation, capitalized	0.1	0.2	0.5	0.4
Unearned Compensation	47.2		$ 47.2		34.4
Expected period to recognize unearned compensation (in years)			2 years 9 months 18 days
Service-Based Restricted Stock Units
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	5.3	3.6	$ 9.2	6.8
Deferred compensation, capitalized	0.9	0.8	1.6	1.6
Unearned Compensation	57.6		$ 57.6		41.5
Expected period to recognize unearned compensation (in years)			2 years 9 months 18 days
Interxion awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Deferred compensation, expensed	4.1	$ 7.1	$ 14.6	$ 10.1
Unearned Compensation	$ 12.8		$ 12.8		$ 27.2
Expected period to recognize unearned compensation (in years)			1 year 10 months 24 days