Property, plant and equipment, at December 31, consist of the following:
 
2016
2015
Land and improvements
$
42,654

$
42,654

Buildings and improvements
330,254

325,580

Machinery and equipment
1,374,551

1,349,731

Construction in progress
21,106

173,418

 
1,768,565

1,891,383

Less accumulated depreciation
(742,280
)
(659,127
)
Property, plant and equipment - net
$
1,026,285

$
1,232,256