Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
OPERATING ACTIVITIES
Net income	$ 187.3	$ 62.9	$ 262.3	$ 239.2
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense			105.7	88.2
Accretion of discount on notes receivable from ARO			(18.5)	(33.8)
Share-based compensation expense			18.4	22.4
Equity in losses (earnings) of ARO	(4.4)	23.8	(5.9)	21.7
Deferred income tax expense	(0.8)	3.8	172.5	19.3
Net (gain) loss on sale of property			(117.4)	0.3
Loss on impairment	0.0	0.0	7.8	0.0
Changes in contract liabilities			(39.3)	(13.5)
Changes in deferred costs			9.1	32.6
Other			6.1	5.0
Changes in operating assets and liabilities			86.3	(131.0)
Contributions to pension plans and other post-retirement benefits			(13.1)	(19.6)
Net cash provided by operating activities			474.0	230.8
INVESTING ACTIVITIES
Additions to property and equipment			(237.2)	(343.4)
Proceeds from disposition of assets			136.3	0.2
Net cash used in investing activities			(100.9)	(343.2)
FINANCING ACTIVITIES
Payments for share repurchases			(75.0)	(101.4)
Payments related to tax withholdings for share-based awards			(3.1)	(29.7)
Net cash used in financing activities			(78.1)	(131.1)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH			295.0	(243.5)
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING OF PERIOD			380.5	635.7
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, END OF PERIOD	$ 675.5	$ 392.2	$ 675.5	$ 392.2

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