Property, Plant and Equipment

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment are comprised of the following at December 31:

	Useful Life	2018		2017
Land and improvements (1)	8 - 20 years (1)	$	432	$	413
Buildings, structures and related equipment	5 - 40 years	2,854		3,168
Machinery, equipment and other	2 - 20 years	6,567		6,195
Total cost		9,853		9,776
Less: Accumulated depreciation		3,625		2,817
Property, plant and equipment, less accumulated depreciation		$	6,228	$	6,959

⁽¹⁾  Useful life excludes land.

Depreciation expense relating to property, plant and equipment was $1,031 million, $716 million and $311 million in 2018, 2017 and 2016, respectively. See "Note 20. Restructuring, impairment and other" for additional information on property, plant and equipment impairments.