Condensed Consolidating Financial Statements - Condensed Consolidating Statement of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	$ 99,577	$ 173,635	$ 112,846
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(66,046)	(103,047)	(58,752)
Proceeds from disposals of plant, equipment and timberlands, net	5,072	1,947	10,272
Acquisitions, net of cash acquired	(8,015)	(210,911)
Other	(600)	(425)	(225)
Net cash used by investing activities	(69,589)	(312,436)	(48,705)
Financing activities
Net (repayments of) proceeds from indebtedness	(18,128)	182,230	17,869
Payments of note offering costs		(419)us-gaap_PaymentsOfDebtIssuanceCosts	(4,748)us-gaap_PaymentsOfDebtIssuanceCosts
Payment of dividends to shareholders	(18,696)us-gaap_PaymentsOfDividendsCommonStock	(16,965)us-gaap_PaymentsOfDividendsCommonStock	(15,608)us-gaap_PaymentsOfDividendsCommonStock
Repurchases of common stock	(12,180)		(5,675)
Payments related to share-based compensation awards and other	(1,877)	(1,671)	2,673
Net cash (used) provided by financing activities	(50,881)	163,175	(5,489)
Effect of exchange rate on cash	(2,152)	829	750
Net (decrease) increase in cash and cash equivalents	(23,045)	25,203	59,402
Cash and cash equivalents at the beginning of period	122,882	97,679	38,277
Cash and cash equivalents at the end of period	99,837	122,882	97,679
Net (decrease) increase in cash and cash equivalents	(23,045)	25,203	59,402
Adjustments/ Eliminations [Member]
Investing activities
Repayments from intercompany loans	(20,840)	(18,223)	(35,431)
Advances of intercompany loans	39,011	27,216	34,980
Intercompany capital contributed		91
Net cash used by investing activities	18,171	9,084	(451)
Financing activities
Repayments of intercompany loans	20,840	18,223	35,431
Borrowings of intercompany loans	(39,011)	(27,216)	(34,980)
Intercompany capital received		(91)
Net cash (used) provided by financing activities	(18,171)	(9,084)	451
Parent Company [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	36,240	55,507	25,787
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(34,518)	(39,496)	(23,463)
Proceeds from disposals of plant, equipment and timberlands, net	3,707	1,435	10,236
Repayments from intercompany loans			6,088
Advances of intercompany loans	(12,671)		(91)
Other	(600)	(425)	(225)
Net cash used by investing activities	(44,082)	(38,486)	(7,455)
Financing activities
Net (repayments of) proceeds from indebtedness			17,869
Payments of note offering costs		(160)	(4,748)
Payment of dividends to shareholders	(18,696)	(16,965)	(15,608)
Repurchases of common stock	(12,180)		(5,675)
Repayments of intercompany loans		(1,100)
Borrowings of intercompany loans	26,340	15,310	27,875
Payments related to share-based compensation awards and other	(1,630)	(1,671)	2,673
Net cash (used) provided by financing activities	(6,166)	(4,586)	22,386
Net (decrease) increase in cash and cash equivalents			40,718
Cash and cash equivalents at the beginning of period	56,216	43,781	3,063
Cash and cash equivalents at the end of period	42,208	56,216	43,781
Net (decrease) increase in cash and cash equivalents			40,718
Guarantors [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	4,158	4,974	5,958
Investing activities
Proceeds from disposals of plant, equipment and timberlands, net	1,355	333
Repayments from intercompany loans	20,840	18,223	29,343
Advances of intercompany loans	(26,340)	(27,216)	(34,375)
Intercompany capital contributed		(91)
Net cash used by investing activities	(4,145)	(8,751)	(5,032)
Financing activities
Borrowings of intercompany loans			514
Net cash (used) provided by financing activities			514
Net (decrease) increase in cash and cash equivalents			1,440
Cash and cash equivalents at the beginning of period	501	4,278	2,838
Cash and cash equivalents at the end of period	514	501	4,278
Net (decrease) increase in cash and cash equivalents			1,440
Non Guarantors [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided (used) by Operating activities	59,179	113,154	81,101
Investing activities
Expenditures for purchases of plant, equipment and timberlands	(31,528)	(63,551)	(35,289)
Proceeds from disposals of plant, equipment and timberlands, net	10	179	36
Advances of intercompany loans			(514)
Acquisitions, net of cash acquired	(8,015)	(210,911)
Net cash used by investing activities	(39,533)	(274,283)	(35,767)
Financing activities
Net (repayments of) proceeds from indebtedness	(18,128)	182,230
Payments of note offering costs		(259)
Repayments of intercompany loans	(20,840)	(17,123)	(35,431)
Borrowings of intercompany loans	12,671	11,906	6,591
Intercompany capital received		91
Payments related to share-based compensation awards and other	(247)
Net cash (used) provided by financing activities	(26,544)	176,845	(28,840)
Effect of exchange rate on cash	(2,152)	829	750
Net (decrease) increase in cash and cash equivalents			17,244
Cash and cash equivalents at the beginning of period	66,165	49,620	32,376
Cash and cash equivalents at the end of period	57,115	66,165	49,620
Net (decrease) increase in cash and cash equivalents			$ 17,244

Payments for intercompany capital contributed.

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Proceeds from intercompany capital contributed.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash outflow to reacquire common stock during the period.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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