SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financial information of segments
SALES	$ 268,694	$ 294,700	$ 525,514	$ 579,329
OPERATING PROFIT	22,230	33,474	45,264	65,323
Operating Segments
Financial information of segments
SALES	268,694	294,700	525,514	579,329
INTERSEGMENT SALES	2,592	4,249	5,915	8,382
Corporate
Financial information of segments
OPERATING PROFIT	(3,278)	(4,405)	(6,895)	(9,594)
Office \| Operating Segments
Financial information of segments
SALES	153,042	179,270	302,874	364,626
INTERSEGMENT SALES	450	488	724	1,069
OPERATING PROFIT	4,395	15,794	13,171	35,627
Restructuring charges	2,200		2,200
Studio \| Operating Segments
Financial information of segments
SALES	88,039	88,650	167,112	160,156
INTERSEGMENT SALES	1,493	1,753	2,591	3,058
OPERATING PROFIT	14,919	15,627	26,558	26,110
Coverings \| Operating Segments
Financial information of segments
SALES	27,613	26,780	55,528	54,547
INTERSEGMENT SALES	649	2,008	2,600	4,255
OPERATING PROFIT	$ 6,194	$ 6,458	$ 12,430	$ 13,180

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
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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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