Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Accounts receivable, allowance	$ 5.1	$ 2.8
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	129,289,960	127,807,546
Common stock, shares outstanding (in shares)	115,374,788	114,021,280
Treasury stock, shares (in shares)	13,915,172	13,786,266
Related Party
Accounts receivable, allowance	$ 0.1	$ 0.0
Redeemable Convertible Preferred Stock
Preferred stock, dividend rate (percentage)	8.00%	8.00%
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	370,000	370,000
Preferred stock, shares issued (in shares)	277,296	266,529
Preferred stock, shares outstanding (in shares)	277,296	266,529
Preferred stock, aggregate liquidation value	$ 282.8	$ 271.9

Amount of allowance for credit loss on accounts receivable, classified as current.

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