SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Financial information of segments
NET SALES	$ 263,588	$ 268,297	$ 798,708	$ 763,841
INTERSEGMENT SALES	3,495	4,850	10,724	14,081
OPERATING PROFIT	28,704	23,315	79,258	56,837
Restructuring charges	441	0	441	795
Office
Financial information of segments
NET SALES	160,781	166,788	489,381	471,971
INTERSEGMENT SALES	343	837	1,244	1,821
OPERATING PROFIT	11,112	8,351	27,457	15,223
Restructuring charges			0	800
Studio
Financial information of segments
NET SALES	74,965	72,236	223,022	204,687
INTERSEGMENT SALES	1,525	1,575	4,611	4,409
OPERATING PROFIT	11,340	9,003	32,371	24,052
Restructuring charges			441
Coverings
Financial information of segments
NET SALES	27,842	29,273	86,305	87,183
INTERSEGMENT SALES	1,627	2,438	4,869	7,851
OPERATING PROFIT	$ 6,252	$ 5,961	19,430	$ 17,562
Restructuring charges			$ 0

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.

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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).

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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