CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net income	$ 9.7	$ 22.0
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation and amortization	88.9	124.7
Deferred income taxes	(3.9)	2.3
Provision for doubtful accounts	0.7	5.3
Gain on sale of operating assets, net	(1.0)
Amortization of debt issuance costs and discount	0.8	2.4
Non-cash compensation	12.1	7.1
Other non-cash items	0.1	(0.2)
Changes in operating assets and liabilities:
Receivables and other operating assets	(8.4)	(9.3)
Payables and accruals	(150.7)	2.6
Net cash (used in) provided by operating activities	(51.7)	156.9
Cash flows from investing activities:
Capital expenditures	(76.8)	(115.5)
Other investing activities	1.1	0.9
Net cash used in investing activities	(75.7)	(114.6)
Cash flows from financing activities:
Proceeds from issuance of long-term debt, net		31.0
Payments on long-term debt and finance lease obligations	(9.9)	(55.0)
Purchase of shares	(6.0)	(7.4)
Net cash used in financing activities	(15.9)	(31.4)
(Decrease) increase in cash and cash equivalents	(143.3)	10.9
Cash and cash equivalents, beginning of period	193.2	12.4
Cash and cash equivalents, end of period	49.9	23.3
Supplemental disclosures of cash flow information:
Cash paid during the periods for interest	14.4	59.0
Cash paid during the periods for income taxes	141.0	1.7
Non-cash operating activities
Operating lease additions	1.5	0.9
Non-cash financing activities:
Finance lease additions	6.2	3.3
Capital expenditure accounts payable and accruals	$ 22.3	$ 12.2