Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 240.4	$ 256.4
Accounts receivable—trade, less allowance for doubtful accounts of $0.1 at 2022 and 2021	296.8	195.7
Inventories, at lower of cost or market	314.0	292.3
Prepaid expenses and other current assets	31.1	23.4
Total current assets	882.3	767.8
Property, plant and equipment, at cost less accumulated depreciation and amortization of $1,471.8 and $1,373.4 at 2022 and 2021, respectively	2,409.6	2,378.4
Operating lease right of use assets, net	443.7	419.2
Intangible assets, net of amortization	140.5	140.7
Goodwill	328.0	328.0
Other assets	13.7	14.1
Total assets	4,217.8	4,048.2
Current liabilities
Current maturities of long-term debt	14.9	15.0
Trade accounts payable and accrued liabilities	836.8	660.3
Income taxes payable	1.0	0.0
Total current liabilities	852.7	675.3
Long-term debt, including capitalized lease obligations	1,795.5	1,800.1
Deferred income taxes	309.2	295.9
Asset retirement obligations	40.1	39.2
Non current operating lease liabilities	435.2	408.9
Deferred credits and other liabilities	22.4	21.6
Total liabilities	3,455.1	3,241.0
Stockholders' Equity
Preferred Stock, par $0.01, (authorized 20,000,000 shares, none outstanding)	0.0	0.0
Common Stock, par $0.01, (authorized 200,000,000 shares, 46,767,164 shares issued at 2022 and 2021 respectively)	0.5	0.5
Treasury stock (22,565,573 and 21,831,904 shares held at 2022 and 2021, respectively)	(2,183.4)	(1,839.3)
Additional paid in capital (APIC)	513.1	534.8
Retained earnings	2,433.3	2,112.4
Accumulated other comprehensive income (loss) (AOCI)	(0.8)	(1.2)
Total stockholders' equity	762.7	807.2
Total liabilities and stockholders' equity	$ 4,217.8	$ 4,048.2