Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash Flows from Operating Activities:
Net income	$ 555.7	$ 373.8
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, and amortization of intangibles	224.0	205.5
Amortization of deferred financing costs	1.0	1.3
Share-based compensation expense	21.6	20.1
Deferred income tax provision	28.8	14.3
Loss on asset disposals	12.1	5.4
Pension and post-retirement benefits expense, net of contributions	1.7	(0.3)
Other, net	0.2	4.2
Increase in assets -
Accounts receivable	(140.9)	(149.0)
Inventories	(51.7)	(39.4)
Prepaid expenses and other current assets	(27.3)	(34.7)
Increase (decrease) in liabilities -
Accounts payable	25.1	(2.7)
Accrued liabilities	(18.3)	15.4
Federal and state income taxes payable / receivable	12.3	5.9
Net cash provided by operating activities	644.3	419.8
Cash Flows from Investing Activities:
Additions to property, plant, and equipment	(397.5)	(216.5)
Additions to other long term assets	(2.6)	(1.6)
Proceeds from asset disposals	0.4	2.4
Purchases of marketable debt securities	(64.2)	(65.7)
Proceeds from sales of marketable debt securities	19.9	12.9
Proceeds from maturities of marketable debt securities	44.0	48.3
Other, net	1.9	0.0
Net cash used for investing activities	(398.1)	(220.2)
Cash Flows from Financing Activities:
Repayments of debt and finance lease obligations	(0.9)	(0.8)
Financing costs paid	0.0	(0.9)
Common stock dividends paid	(187.2)	(189.8)
Shares withheld to cover employee restricted stock taxes	(9.5)	(10.5)
Net cash used for financing activities	(197.6)	(202.0)
Net increase (decrease) in cash and cash equivalents	48.6	(2.4)
Cash and cash equivalents, beginning of period	618.7	974.6
Cash and cash equivalents, end of period	$ 667.3	$ 972.2