Statements of Consolidated Cash Flows (Unaudited) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022
Operating Activities:
Net income (loss)		$ (69.3)	$ 32.5
Adjustments to reconcile net loss to cash flows from operating activities:
Depreciation and amortization		71.1	71.2
Lease amortization and accretion expense	[1]	38.7	52.8
Lease payments		(38.1)	(53.4)
Paid-in-kind interest		11.3	4.7
Debt-related amortization		11.7	11.7
Equity-based compensation and employee benefits expense		6.9	7.4
Non-union pension settlement charges		0.1	0.0
Gains on property disposals, net		(76.4)	(8.7)
Deferred income taxes, net		1.0	0.0
Other non-cash items, net		0.3	(0.2)
Changes in assets and liabilities, net:
Accounts receivable		64.7	(120.5)
Accounts payable		(31.0)	44.9
Other operating assets		7.9	13.6
Other operating liabilities		8.8	(19.4)
Net cash provided by (used in) operating activities		7.7	36.6
Investing Activities:
Acquisition of property and equipment		(45.6)	(72.6)
Proceeds from disposal of property and equipment		3.5	9.4
Net cash provided by (used in) investing activities		(42.1)	(63.2)
Financing Activities:
Repayment of debt		(71.9)	(12.4)
Payments for tax withheld on equity-based compensation		(0.3)	(0.6)
Net cash provided by (used in) financing activities		(72.2)	(13.0)
Net Increase (Decrease) In Cash and Cash Equivalents and Restricted Amounts Held in Escrow		(106.6)	(39.6)
Cash and Cash Equivalents and Restricted Amounts Held in Escrow, Beginning of Period		239.0	314.8
Cash and Cash Equivalents and Restricted Amounts Held in Escrow, End of Period		132.4	275.2
Supplemental Cash Flow Information:
Interest paid		$ (86.2)	$ (71.0)

[1] Operating lease cost represents non-cash amortization of ROU assets and accretion of the discounted lease liabilities and is segregated on the statements of consolidated cash flows.