Condensed Consolidating Financial Statements - Condensed Consolidating Statement of Income (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Income Statements, Captions [Line Items]
Net sales	$ 229,480	$ 209,855	$ 215,742	$ 211,209	$ 209,327	$ 210,120	$ 195,974	$ 184,941	$ 866,286	$ 800,362	$ 761,216
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	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	$ 30,674	$ 29,872	$ 33,300	$ 36,561	$ 38,337	$ 37,375	$ 35,096	$ 32,781	$ 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)
Other 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	$ (3,289)	$ (705)	$ 1,278	$ 2,268	$ (14,699)	$ 5,045	$ 2,341	$ 1,701	(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
Other comprehensive income (loss)									25,533	63,931	(14,120)
Comprehensive income (loss)									(152,071)	71,845	7,434
Income tax provision									(30,086)	6,342	17,657
Adjustments/ Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Net sales									$ (102,435)	$ (88,028)	$ (69,644)
Type of Revenue [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs of products sold									$ (102,435)	$ (88,028)	$ (69,644)
Type of Cost, Good or Service [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Other non-operating income (expense)
Interest expense									$ 13,366	$ 5,394	$ 4,715
Interest income									(13,366)	(5,394)	(4,715)
Equity in earnings of subsidiaries									(105,405)	(79,735)	(119,354)
Total non-operating expense									(105,405)	(79,735)	(119,354)
Income (loss) before income taxes									(105,405)	(79,735)	(119,354)
Loss from continuing operations									(105,405)	(79,735)
Discontinued operations:
Net income (loss)									(105,405)	(79,735)
Other comprehensive income (loss)									45,625	(104,118)	51,092
Comprehensive income (loss)									$ (59,780)	$ (183,853)	$ 51,092
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Type of Revenue [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs of products sold									$ 3,746	$ 598	$ 240
Type of Cost, Good or Service [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Gross profit									$ (3,746)	$ (598)	$ (240)
Selling, general and administrative expenses									45,491	45,623	95,846
Losses (gains) on dispositions of plant, equipment and timberlands, net									(16)		77
Operating income (loss)									(49,221)	(46,221)	(96,163)
Other non-operating income (expense)
Interest expense									(23,527)	(15,939)	(15,464)
Interest income									7,070	599	687
Equity in earnings of subsidiaries									53,684	18,864	61,007
Other, net									(714)	2,756	(8,459)
Total non-operating expense									36,513	6,280	37,771
Income (loss) before income taxes									(12,708)	(39,941)	(58,392)
Income tax provision (benefit)									(12,260)	(34,329)	(44,215)
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
Other comprehensive income (loss)									25,533	63,931	(14,120)
Comprehensive income (loss)									(152,071)	71,845	7,434
Income tax provision									(30,086)	6,342	17,657
Guarantors [Member]
Condensed Income Statements, Captions [Line Items]
Net sales									$ 124,716	$ 89,787	$ 75,000
Type of Revenue [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs of products sold									$ 117,867	$ 85,196	$ 70,991
Type of Cost, Good or Service [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Gross profit									$ 6,849	$ 4,591	$ 4,009
Selling, general and administrative expenses									1,856	2,598	156
Losses (gains) on dispositions of plant, equipment and timberlands, net									(3,225)	(188)
Operating income (loss)									8,218	2,181	4,165
Other non-operating income (expense)
Interest expense									(2,784)	(971)	(41)
Interest income									6,238	4,947	4,177
Equity in earnings of subsidiaries									51,721	60,871	58,347
Other, net									(6,862)	(6,776)	(3,966)
Total non-operating expense									48,313	58,071	58,517
Income (loss) before income taxes									56,531	60,252	62,682
Income tax provision (benefit)									3,079	41,388	1,675
Loss from continuing operations									53,452	18,864	61,007
Discontinued operations:
Net income (loss)									53,452	18,864	61,007
Other comprehensive income (loss)									(22,411)	52,290	(25,916)
Comprehensive income (loss)									31,041	71,154	35,091
Non Guarantors [Member]
Condensed Income Statements, Captions [Line Items]
Net sales									$ 844,005	$ 798,603	$ 755,860
Type of Revenue [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Costs of products sold									$ 716,701	$ 659,007	$ 627,880
Type of Cost, Good or Service [Extensible List]									us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Gross profit									$ 127,304	$ 139,596	$ 127,980
Selling, general and administrative expenses									64,374	62,313	57,463
Losses (gains) on dispositions of plant, equipment and timberlands, net									(15)	(9)	39
Operating income (loss)									62,945	77,292	70,478
Other non-operating income (expense)
Interest expense									(2,664)	(1,801)	(3,060)
Interest income									617	85	57
Other, net									7,959	3,315	5,007
Total non-operating expense									5,912	1,599	2,004
Income (loss) before income taxes									68,857	78,891	72,482
Income tax provision (benefit)									16,904	18,020	14,135
Loss from continuing operations									51,953	60,871	58,347
Discontinued operations:
Net income (loss)									51,953	60,871	58,347
Other comprehensive income (loss)									(23,214)	51,828	(25,176)
Comprehensive income (loss)									$ 28,739	$ 112,699	$ 33,171