DEBT (Tables)	9 Months Ended
	Sep. 30, 2021
DEBT [Abstract]
Debt	Effective September 30 December 31 September 30 in thousandsInterest Rates 2021 2020 2020 Short-term Debt Bank line of credit expires 2025 1 $                  0  $                0  $                0  Total short-term debt $                  0  $                0  $                0  Long-term Debt Bank line of credit expires 2025 1 $                  0  $                0  $                0  Delayed draw term loan expires 20241.21% 1,100,000  0  0  Floating-rate notes due 2021 0  500,000  500,000  8.85% notes due 20218.88% 6,000  6,000  6,000  4.50% notes due 20254.65% 400,000  400,000  400,000  3.90% notes due 20274.00% 400,000  400,000  400,000  3.50% notes due 20303.94% 750,000  750,000  750,000  7.15% notes due 20378.05% 129,239  129,239  129,239  4.50% notes due 20474.59% 700,000  700,000  700,000  4.70% notes due 20485.42% 460,949  460,949  460,949  Other notes2.45% 11,020  11,711  11,718  Total long-term debt - face value $    3,957,208  $  3,357,899  $  3,357,906  Unamortized discounts and debt issuance costs (70,864) (70,224) (71,399) Total long-term debt - book value $    3,886,344  $  3,287,675  $  3,286,507  Less current maturities 12,228  515,435  509,435  Total long-term debt - reported value $    3,874,116  $  2,772,240  $  2,777,072  Estimated fair value of long-term debt $    4,442,119  $  3,443,225  $  3,341,097  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.
Standby Letters of Credit	in thousands Standby Letters of Credit Risk management insurance$       74,794  Reclamation/restoration requirements 8,391  Total$       83,185