Redeemable Series A Preferred Units (Details) - USD ($) $ in Millions		3 Months Ended
	Jun. 08, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Series A Preferred Unit redemption accretion			$ 74.0
Series A Preferred Units, carrying amount		$ 0.0		$ 200.2
Additional Paid-in Capital
Class of Stock [Line Items]
Series A Preferred Unit redemption accretion		$ 74.0	$ 74.0
Redeemable Series A Preferred Units
Class of Stock [Line Items]
Outstanding preferred units redeemed and cancelled	$ 274.2
Series A Preferred Units, carrying amount	200.2
Series A Preferred Units, accreted but unpaid dividends	45.4
Series A Preferred Units, excess amount due upon early redemption	28.6
Series A Preferred Units, excess amount due upon early redemption, noncontrolling interests	17.6
Series A Preferred Units, excess amount due upon early redemption, common stock	$ 11.0