SEGMENT INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Financial information of segments
NET SALES	$ 266,498us-gaap_SalesRevenueNet	$ 229,601us-gaap_SalesRevenueNet
INTERSEGMENT SALES	3,791us-gaap_Revenues	4,398us-gaap_Revenues
OPERATING PROFIT	22,299us-gaap_OperatingIncomeLoss	11,284us-gaap_OperatingIncomeLoss
Restructuring and other charges	0us-gaap_RestructuringCharges	592us-gaap_RestructuringCharges
Operating Segments
Financial information of segments
OPERATING PROFIT	22,299	11,876
Office
Financial information of segments
NET SALES	167,723	146,083
INTERSEGMENT SALES	486	473
OPERATING PROFIT	7,246	1,062
Studio
Financial information of segments
NET SALES	70,194	55,997
INTERSEGMENT SALES	1,380	1,310
OPERATING PROFIT	8,952	5,543
Coverings
Financial information of segments
NET SALES	28,581	27,521
INTERSEGMENT SALES	1,925	2,615
OPERATING PROFIT	$ 6,101	$ 5,271

The net result for the period of deducting operating expenses from operating revenues.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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-Publisher FASB

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-Topic 225

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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