PROPERTY, PLANT & EQUIPMENT

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

PROPERTY, PLANT & EQUIPMENT

PROPERTY, PLANT & EQUIPMENT

The major classes of depreciable assets are as follows:

	December 31,
In thousands	2015			2014
Machinery and equipment	$	502,086		$	476,467
Buildings and improvements	170,668			180,227
Land and improvements	41,671			23,440
Locomotive leased fleet	2,870			2,900
PP&E	717,295			683,034
Less: accumulated depreciation	(364,102		)	(343,923		)
Total	$	353,193		$	339,111

The estimated useful lives of property, plant and equipment are as follows:

	Years
Land improvements	10 to 20
Building and improvements	20 to 40
Machinery and equipment	3 to 15

Depreciation expense was $43.1 million, $38.8 million, and $33.5 million for 2015, 2014 and 2013, respectively.