Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash Flows from Operating Activities:
Net income	$ 338.9	$ 332.6
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, and amortization of intangibles	264.3	267.9
Amortization of deferred financing costs	5.8	5.8
Share-based compensation expense	15.0	13.7
Deferred income tax provision	6.5	1.2
Pension and postretirement benefits expense, net of contributions	(33.5)	24.0
Other, net	3.7	(16.4)
Decrease (increase) in assets —
Accounts receivable	(36.0)	(37.5)
Inventories	4.1	(31.0)
Prepaid expenses and other current assets	(11.2)	(16.8)
Increase (decrease) in liabilities —
Accounts payable	13.6	(14.1)
Accrued liabilities	10.8	5.2
Federal and state income taxes payable / receivable	6.2	7.4
Net cash provided by operating activities	588.2	542.0
Cash Flows from Investing Activities:
Additions to property, plant, and equipment	(188.1)	(217.9)
Proceeds from sale of a business	0.0	23.0
Acquisition of business, net of cash acquired	(385.6)	0.0
Additions to other long-term assets	(9.4)	(9.2)
Other, net	0.4	1.3
Net cash used for investing activities	(582.7)	(202.8)
Cash Flows from Financing Activities:
Repayments of debt and capital lease obligations	(30.7)	(30.7)
Proceeds from issuance of debt	385.0	0.0
Financing costs paid	(2.1)	0.0
Common stock dividends paid	(156.7)	(147.3)
Repurchases of common stock	(100.3)	(98.1)
Excess tax benefits from stock-based awards	5.3	5.6
Shares withheld to cover employee restricted stock taxes	(10.2)	(7.4)
Other, net	(0.2)	0.7
Net cash provided by (used for) financing activities	90.1	(277.2)
Net increase in cash and cash equivalents	95.6	62.0
Cash and cash equivalents, beginning of period	184.2	124.9
Cash and cash equivalents, end of period	$ 279.8	$ 186.9