COMMITMENTS AND CONTINGENCIES (Tables)

12 Months Ended

Dec. 31, 2018

COMMITMENTS AND CONTINGENCIES [Abstract]

Commitments Due

	Unconditional
	Purchase
in thousands	Obligations
Property, Plant & Equipment
2019	$        35,248
Thereafter	0
Total	$        35,248
Noncapital (primarily transportation and electricity contracts)
2019	$        11,912
2020–2021	9,120
2022–2023	3,690
Thereafter	12,000
Total	$        36,722

Minimum Royalties Under Mineral Leases

	Mineral
in thousands	Leases
Minimum Royalties
2019	$        23,211
2020–2021	36,630
2022–2023	26,014
Thereafter	154,720
Total	$      240,575