Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Allowances for accounts and notes receivable	$ 18.2	$ 14.3
Property and equipment, accumulated depreciation and amortization	$ 585.1	$ 474.5
Common stock, par value (in usd per share)
Common stock, shares authorized	Unlimited	Unlimited
Common stock, shares issued	237,278,477	234,236,678
Common stock, shares outstanding	237,278,477	234,236,678
Redeemable Preferred Stock
Preferred stock, par value (in usd per share)
Preferred stock, shares authorized	68,530,939	68,530,939
Preferred stock, shares issued	68,530,939	68,530,939
Preferred stock, shares outstanding	68,530,939	68,530,939

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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