CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (18.4)	$ 339.5
Adjustments to reconcile net income (loss) to net cash provided by operations:
Depreciation and amortization	200.6	199.0
Deferred income taxes	36.4	(5.2)
Provision for pension and other postretirement benefits	5.1	9.5
Share-based compensation expense	12.2	17.5
Loss on disposals of property and equipment	6.5	4.1
Contingent payment derivative	0.1	(6.4)
Other	1.3	0.4
Changes in current assets and liabilities:
Receivables - trade and other	(15.2)	(139.9)
Prepaid expenses and other current assets	0.2	(3.8)
Accounts payable	1.1	11.2
Accrued income taxes	5.1	14.9
Other current liabilities	(17.7)	(18.0)
Other postretirement benefit claims paid	(1.8)	(4.9)
Contributions to pension plans	(12.0)	(8.2)
Deferred revenues	(39.9)	(9.4)
Net changes in other noncurrent assets and liabilities	(25.1)	(7.1)
Net cash provided by operating activities	138.5	393.2
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(57.3)	(64.4)
Investment in unconsolidated subsidiary	(25.0)	0.0
Proceeds from disposals of property and equipment	1.3	1.1
Net cash used in investing activities	(81.0)	(63.3)
CASH FLOWS FROM FINANCING ACTIVITIES:
Reductions of long-term debt	(163.4)	(47.9)
Shares repurchased for tax withholdings on vesting of restricted share units	(4.4)	(4.8)
Net cash used in financing activities	(167.8)	(52.7)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(110.3)	277.2
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	1,255.5	484.2
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 1,145.2	$ 761.4