Condensed Consolidating Financial Statements - Condensed Consolidating Statement of Cash Flows (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	$ 36,640	$ 25,513
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(80,391)	(44,575)
Proceeds from disposals of plant, equipment and timberlands, net	53	3,051
Other	(300)	(1,600)
Net cash used by investing activities	(80,638)	(43,124)
Financing activities
Net long-term borrowings	4,222	(1,492)
Payments of borrowing costs	(136)	(1,329)
Payment of dividends to shareholders	(10,679)	(9,992)
Proceeds from government grants	4,443
Payments related to share-based compensation awards and other	(976)	(2,000)
Net cash used by financing activities	(3,126)	(14,813)
Effect of exchange rate on cash	352	(1,651)
Net increase (decrease) in cash	(46,772)	(34,075)
Cash and cash equivalents at the beginning of period	105,304	99,837
Cash and cash equivalents at the end of period	58,532	65,762
Adjustments/ Eliminations [Member]
Investing activities
Repayments from intercompany loans	(7,500)	(48,855)
Advances of intercompany loans	7,880	38,690
Intercompany capital (contributed) returned	17,500	(10,200)
Net cash used by investing activities	17,880	(20,365)
Financing activities
Repayments of intercompany loans	7,500	48,855
Borrowings of intercompany loans	(7,880)	(38,690)
Intercompany capital (returned) received	(17,500)	10,200
Net cash used by financing activities	(17,880)	20,365
Parent Company [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	17,067	(4,343)
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(51,043)	(30,241)
Proceeds from disposals of plant, equipment and timberlands, net	41	1,581
Intercompany capital (contributed) returned	(17,000)	10,500
Other	(300)	(1,600)
Net cash used by investing activities	(68,302)	(19,760)
Financing activities
Payments of borrowing costs	(51)	(1,329)
Payment of dividends to shareholders	(10,679)	(9,992)
Repayments of intercompany loans		(9,158)
Borrowings of intercompany loans	7,880	38,690
Proceeds from government grants	2,443
Payments related to share-based compensation awards and other	(976)	(2,000)
Net cash used by financing activities	(1,383)	16,211
Net increase (decrease) in cash	(52,618)	(7,892)
Cash and cash equivalents at the beginning of period	59,130	42,208
Cash and cash equivalents at the end of period	6,512	34,316
Guarantors [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	2,821	(695)
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(18,861)
Proceeds from disposals of plant, equipment and timberlands, net		1,213
Repayments from intercompany loans	7,500	48,855
Advances of intercompany loans	(7,880)	(38,690)
Intercompany capital (contributed) returned	(500)	(300)
Net cash used by investing activities	(19,741)	11,078
Financing activities
Intercompany capital (returned) received	17,000	(10,500)
Proceeds from government grants	2,000
Net cash used by financing activities	19,000	(10,500)
Net increase (decrease) in cash	2,080	(117)
Cash and cash equivalents at the beginning of period	465	509
Cash and cash equivalents at the end of period	2,545	392
Non Guarantors [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	16,752	30,551
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(10,487)	(14,334)
Proceeds from disposals of plant, equipment and timberlands, net	12	257
Net cash used by investing activities	(10,475)	(14,077)
Financing activities
Net long-term borrowings	4,222	(1,492)
Payments of borrowing costs	(85)
Repayments of intercompany loans	(7,500)	(39,697)
Intercompany capital (returned) received	500	300
Net cash used by financing activities	(2,863)	(40,889)
Effect of exchange rate on cash	352	(1,651)
Net increase (decrease) in cash	3,766	(26,066)
Cash and cash equivalents at the beginning of period	45,709	57,120
Cash and cash equivalents at the end of period	$ 49,475	$ 31,054