PROPERTY, PLANT & EQUIPMENT

12 Months Ended

Dec. 31, 2019

PROPERTY, PLANT & EQUIPMENT [Abstract]

NOTE 4: PROPERTY, PLANT & EQUIPMENT

Balances of major classes of assets and allowances for depreciation, depletion and amortization at December 31 are as follows:



in thousands	2019	2018
Property, Plant & Equipment
Land and land improvements ¹	$ 2,920,963	$ 2,823,092
Buildings	141,898	139,948
Machinery and equipment	5,362,279	5,106,918
Leasehold improvements	1,677	18,217
Deferred asset retirement costs	167,484	183,324
Construction in progress	154,917	186,120
Total, gross	$ 8,749,218	$ 8,457,619
Less allowances for depreciation, depletion
and amortization	4,433,180	4,220,312
Total, net	$ 4,316,038	$ 4,237,307


¹	Includes depletable land: December 31, 2019 — $1,667,642 thousand and December 31, 2018 — $1,626,899 thousand.

Capitalized interest costs with respect to qualifying construction projects and total interest costs incurred before recognition of the capitalized amount for the years ended December 31 are as follows:



in thousands	2019	2018	2017
Capitalized interest cost	$ 3,896	$ 3,674	$ 5,177
Total interest cost incurred before recognition
of the capitalized amount ¹	134,051	141,651	300,699


¹	Interest expense for 2017 includes $148,030 thousand of charges related to debt purchases.