Segment and Geographic Information - Schedule of Net Sales to External Customers and Location of Net Plant, Equipment and Timberlands (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 399,917	$ 413,325	$ 387,342	$ 390,713	$ 390,865	$ 405,301	$ 406,413	$ 402,218	$ 1,591,297	$ 1,604,797	$ 1,661,084
Plant, Equipment and Timberlands – Net	865,743				775,898				865,743	775,898	698,864
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									880,708	918,567	959,730
Plant, Equipment and Timberlands – Net	456,223				391,977				456,223	391,977	287,447
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									450,668	427,520	444,009
Plant, Equipment and Timberlands – Net	240,932				220,380				240,932	220,380	232,340
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									76,594	78,759	86,442
Plant, Equipment and Timberlands – Net	55,495				51,903				55,495	51,903	62,931
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									120,434	115,902	118,568
Plant, Equipment and Timberlands – Net	78,220				79,727				78,220	79,727	81,201
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									62,893	64,049	52,335
Plant, Equipment and Timberlands – Net	$ 34,873				$ 31,911				$ 34,873	$ 31,911	$ 34,945