Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Statement of Financial Position [Abstract]
Accumulated depreciation	$ 152.0	$ 110.7
Redeemable preferred stock, shares authorized (shares)	310,000	310,000
Redeemable preferred stock, shares issued (shares)	310,000	310,000
Redeemable preferred stock, shares outstanding (shares)		310,000	310,000
Redeemable preferred stock, redemption value	$ 414.2	$ 395.0
Preferred stock, par value (in USD per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (shares)	20,000,000	20,000,000
Preferred stock, shares issued (shares)	0	0
Preferred stock, shares outstanding (shares)	0	0
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (shares)	300,000,000	300,000,000
Common stock, shares issued (shares)	50,551,483	49,298,940
Common stock, shares outstanding (shares)	50,551,483	49,298,940

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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