Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash Flows from Operating Activities:
Net income	$ 204.8	$ 189.6
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, and amortization of intangibles and deferred financing costs	184.0	189.1
Share-based compensation expense	9.1	7.6
Deferred income tax provision	7.0	19.6
Pension and postretirement benefits expense, net of contributions	15.6	12.7
Other, net	(4.1)	(0.1)
Increase in assets —
Accounts receivable	(61.9)	(47.6)
Inventories	(2.6)	(13.3)
Prepaid expenses and other current assets	(24.8)	(27.5)
Increase (decrease) in liabilities —
Accounts payable	(10.4)	(6.3)
Accrued liabilities	(20.1)	(9.8)
Federal and state income taxes payable / receivable	7.9	20.1
Net cash provided by operating activities	304.5	334.1
Cash Flows from Investing Activities:
Additions to property, plant, and equipment	(141.9)	(148.2)
Proceeds from sale of a business	23.0	0.0
Acquisition of business, net of cash acquired	0.0	(20.3)
Additions to other long-term assets	(6.1)	(5.9)
Other, net	1.1	3.1
Net cash used for investing activities	(123.9)	(171.3)
Cash Flows from Financing Activities:
Repayments of debt and capital lease obligations	(3.8)	(116.5)
Common stock dividends paid	(93.5)	(78.6)
Repurchases of common stock	(43.3)	0.0
Proceeds from exercise of stock options	0.0	3.7
Excess tax benefits from stock-based awards	5.4	11.6
Shares withheld to cover employee restricted stock taxes	(7.4)	(11.8)
Other, net	0.8	(0.2)
Net cash used for financing activities	(141.8)	(191.8)
Net increase (decrease) in cash and cash equivalents	38.8	(29.0)
Cash and cash equivalents, beginning of period	124.9	191.0
Cash and cash equivalents, end of period	$ 163.7	$ 162.0