Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows from Operating Activities:
Net income	$ 103.7	$ 90.8
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, and amortization of intangibles	88.7	93.4
Amortization of deferred financing costs	1.9	1.9
Share-based compensation expense	5.6	4.2
Deferred income tax provision	8.1	7.4
Pension and postretirement benefits expense, net of contributions	6.4	7.7
Other, net	2.1	(5.4)
Decrease (increase) in assets —
Accounts receivable	5.1	(31.4)
Inventories	(15.7)	(22.2)
Prepaid expenses and other current assets	(13.9)	(4.5)
Increase (decrease) in liabilities —
Accounts payable	0.3	(13.6)
Accrued liabilities	(43.5)	(48.8)
Federal and state income taxes payable / receivable	42.2	28.8
Net cash provided by operating activities	191.0	108.3
Cash Flows from Investing Activities:
Additions to property, plant, and equipment	(52.9)	(55.6)
Additions to other long-term assets	(2.9)	(2.6)
Other	0.3	0.6
Net cash used for investing activities	(55.5)	(57.6)
Cash Flows from Financing Activities:
Repayments of debt and capital lease obligations	(1.9)	(1.9)
Common stock dividends paid	(53.1)	(39.4)
Repurchases of common stock	(100.3)	(7.6)
Excess tax benefits from stock-based awards	0.0	0.3
Shares withheld to cover employee restricted stock taxes	(2.1)	(0.3)
Other	0.0	(0.3)
Net cash used for financing activities	(157.4)	(49.2)
Net (decrease) increase in cash and cash equivalents	(21.9)	1.5
Cash and cash equivalents, beginning of period	184.2	124.9
Cash and cash equivalents, end of period	$ 162.3	$ 126.4