INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2021
INCOME TAXES [Abstract]
Components of Earnings From Continuing Operations before Income Taxes	in millions2021 2020 2019 Earnings from Continuing Operations before Income Taxes Domestic$          871.6  $        733.0  $        734.0  Foreign 2.2  10.8  23.7  Total$          873.8  $        743.8  $        757.7
Provision (Benefit) For Income Taxes from Continuing Operations	in millions2021 2020 2019 Income Tax Expense (Benefit) from Continuing Operations Current Federal$          103.9  $          69.2  $          31.2  State and local 34.6  23.8  24.4  Foreign (5.0) 0.9  3.3  Total$          133.5  $          93.9  $          58.9  Deferred Federal$            39.2  $          50.9  $          67.8  State and local 26.5  10.8  8.7  Foreign 0.9  0.2  (0.2) Total$            66.6  $          61.9  $          76.3  Total expense$          200.1  $        155.8  $        135.2
Sources and Tax Effects of Differences Between Benefit from Income Taxes and Amount Computed by Applying Federal Statutory Income Tax Rate to Earnings from Continuing Operations before Income Taxes	dollars in millions2021 2020 2019 Income tax expense at the federal statutory tax rate$       183.5 21.0% $       156.2 21.0% $       159.1 21.0% Expense (Benefit) from Income Tax Differences Statutory depletion (28.3)-3.2% (24.7)-3.3% (23.0)-3.0% State and local income taxes, net of federal income tax benefit 34.7 4.0% 27.4 3.7% 26.1 3.4% Share-based compensation (6.1)-0.7% (6.9)-0.9% (17.2)-2.3% Uncertain tax positions 2.5 0.3% 1.4 0.2% 1.8 0.2% AL NOL valuation allowance 13.7 1.6% 0.0 0.0% 0.0 0.0% Research and development credit (2.7)-0.3% (2.7)-0.4% (9.5)-1.3% Other, net 2.8 0.2% 5.1 0.6% (2.1)-0.2% Total income tax expense/ Effective tax rate$       200.1 22.9% $       155.8 20.9% $       135.2 17.8%
Components of Net Deferred Income Tax Liability	in millions2021 2020 Deferred Tax Assets Related to Employee benefits$           11.8  $          21.9  Incentive compensation 62.5  58.2  Asset retirement obligations & other reserves 77.9  58.3  State net operating losses 75.0  67.7  Other 59.1  25.4  Total gross deferred tax assets$         286.3  $        231.5  Valuation allowance (53.3) (32.5) Total net deferred tax asset$         233.0  $        199.0  Deferred Tax Liabilities Related to Property, plant & equipment$         794.3  $        622.9  Goodwill/other intangible assets 380.2  252.2  Other 64.4  30.0  Total deferred tax liabilities$      1,238.9  $        905.1  Net deferred tax liability$      1,005.9  $        706.1
Changes in Unrecognized Income Tax Benefits	in millions2021 2020 2019 Unrecognized tax benefits as of January 1$             6.8  $            5.4  $            3.7  Increases for tax positions related to Prior years 0.5  0.4  0.2  Current year 3.9  1.9  3.2  Decreases for tax positions related to Prior years 0.0  0.0  0.0  Expiration of applicable statute of limitations (0.4) (0.9) (1.7) Unrecognized tax benefits as of December 31$           10.8  $            6.8  $            5.4