OPERATING LEASES (Tables)

12 Months Ended

Dec. 31, 2014

OPERATING LEASES [Abstract]

Rental Expense from Continuing Operations under Nonmineral Operating Leases

in thousands	2014	2013	2012
Operating Leases
Minimum rentals	$        42,887	$       40,151	$       36,951
Contingent rentals (based principally on usage)	56,717	44,111	32,705
Total	$        99,604	$       84,262	$       69,656

Future Minimum Operating Lease Payments

in thousands
Future Minimum Operating Lease Payments
2015	$        30,096
2016	28,345
2017	25,207
2018	23,231
2019	18,363
Thereafter	128,294
Total	$      253,536