Property, Plant, and Equipment

3 Months Ended

Mar. 31, 2019

Property Plant And Equipment [Abstract]

Property, Plant, and Equipment

10. Property, Plant, and Equipment

The components of property, plant, and equipment were as follows (dollars in millions):

	March 31,			December 31,
	2019			2018
Land and land improvements	$	165.6		$	161.9
Buildings		806.6			795.5
Machinery and equipment		5,522.0			5,481.6
Construction in progress		193.9			176.7
Other		75.9			75.4
Property, plant and equipment, at cost		6,764.0			6,691.1
Less accumulated depreciation		(3,654.2	)		(3,582.5	)
Property, plant, and equipment, net	$	3,109.8		$	3,108.6

Depreciation expense for the three months ended March 31, 2019 and 2018 was $85.2 million and $94.6 million, respectively. We recognized $0.2 million and $8.3 millionof incremental depreciation expense during the three months ended March 31, 2019 and 2018, respectively, as a result of shortening the useful lives of certain assets primarily related to the Wallula mill restructuring.

At March 31, 2019 and December 31, 2018, purchases of property, plant, and equipment included in accounts payable were $34.3 million and $24.7 million, respectively.