DEBT (Tables)	12 Months Ended
Dec. 31, 2021
DEBT [Abstract]
Debt	Effective in millionsInterest Rates 2021 2020 Short-term Debt Bank line of credit expires 2025 1 $ 0.0 $ 0.0 Total short-term debt $ 0.0 $ 0.0 Long-term Debt Bank line of credit expires 2025 1 $ 0.0 $ 0.0 Delayed draw term loan expires 20241.22% 1,100.0 0.0 Floating-rate notes due 2021 0.0 500.0 8.85% notes due 2021 0.0 6.0 4.50% notes due 20254.65% 400.0 400.0 3.90% notes due 20274.00% 400.0 400.0 3.50% notes due 20303.94% 750.0 750.0 7.15% notes due 20378.05% 129.2 129.2 4.50% notes due 20474.59% 700.0 700.0 4.70% notes due 20485.42% 460.9 460.9 Other notes2.35% 9.5 11.7 Total long-term debt - face value $ 3,949.6 $ 3,357.8 Unamortized discounts and debt issuance costs (69.6) (70.2) Total long-term debt - book value $ 3,880.0 $ 3,287.6 Less current maturities 5.2 515.4 Total long-term debt - reported value $ 3,874.8 $ 2,772.2 Estimated fair value of long-term debt $ 4,418.5 $ 3,443.2 1Borrowings on the bank line of credit are classified as short-term if we intend to repay within twelve months and as long-term if we have the intent and ability to extend payment beyond twelve months.
Schedule of Principal and Interest Debt Payments	in millionsTotal Principal Interest Scheduled Debt Payments (excluding the line of credit) 2022$ 145.3 $ 5.2 $ 140.1 2023 151.5 2.3 149.2 2024 1,243.3 1,100.9 142.4 2025 513.8 400.5 113.3 2026 104.7 0.4 104.3
Standby Letters of Credit	in millions Standby Letters of Credit Risk management insurance$ 76.0 Reclamation/restoration requirements 8.4 Total$ 84.4

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- Definition

Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.

+ References

No definition available.

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- Definition

Tabular disclosure of short-term or long-term contractual arrangements with lenders, including letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Tabular disclosure of maturity and sinking fund requirement for long-term debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123465755&loc=d3e1835-112601

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