Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net sales	$ 866,286	$ 800,362	$ 761,216
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs of products sold	$ 735,879	$ 656,773	$ 629,467
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Gross profit	$ 130,407	$ 143,589	$ 131,749
Selling, general and administrative expenses	111,721	110,534	153,153
Losses (gains) on dispositions of plant, equipment and timberlands, net	(3,256)	(197)	116
Operating income (loss)	21,942	33,252	(21,520)
Non-operating income (expense)
Interest expense	(15,609)	(13,317)	(13,850)
Interest income	559	237	206
Other, net	383	(705)	(7,418)
Total non-operating expense	(14,667)	(13,785)	(21,062)
Income (loss) before income taxes	7,275	19,467	(42,582)
Income tax provision (benefit)	7,723	25,079	(28,405)
Loss from continuing operations	(448)	(5,612)	(14,177)
Discontinued operations:
Income (loss) before income taxes	(207,242)	19,868	53,388
Income tax provision (benefit)	(30,086)	6,342	17,657
Income (loss) from discontinued operations	(177,156)	13,526	35,731
Net income (loss)	$ (177,604)	$ 7,914	$ 21,554
Basic earnings (loss) per share
Income (loss) from continuing operations	$ (0.01)	$ (0.13)	$ (0.33)
Income (loss) from discontinued operations	(4.05)	0.31	0.82
Basic earnings (loss) per share	(4.06)	0.18	0.49
Diluted earnings (loss) per share
Income (loss) from continuing operations	(0.01)	(0.13)	(0.32)
Income (loss) from discontinued operations	(4.05)	0.30	0.81
Diluted earnings (loss) per share	$ (4.06)	$ 0.18	$ 0.49
Weighted average shares outstanding
Basic	43,768	43,609	43,558
Diluted	43,768	44,439	44,129