PROPERTY, PLANT & EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2016

PROPERTY, PLANT & EQUIPMENT [Abstract]

Property, Plant and Equipment

in thousands	2016	2015
Property, Plant & Equipment
Land and land improvements 1	$    2,374,051	$  2,305,801
Buildings	127,369	124,950
Machinery and equipment	4,316,243	4,124,808
Leaseholds	17,595	14,143
Deferred asset retirement costs	168,258	166,252
Construction in progress	182,302	155,333
Total, gross	$    7,185,818	$  6,891,287
Less allowances for depreciation, depletion
and amortization	3,924,380	3,734,997
Total, net	$    3,261,438	$  3,156,290

1 Includes depletable land, as follows: December 31, 2016 — $1,327,402 thousand and December 31, 2015 — $1,296,211 thousand.

Capitalized Interest Costs and Total Interest Costs Incurred

in thousands	2016	2015	2014
Capitalized interest cost	$          7,468	$        2,930	$        2,092
Total interest cost incurred before recognition
of the capitalized amount	141,544	223,518	245,459