SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financial information of segments
SALES	$ 294,700	$ 268,622	$ 579,329	$ 535,120
OPERATING PROFIT	33,474	28,255	65,323	50,554
Operating Segments
Financial information of segments
SALES	294,700	268,622	579,329	535,120
INTERSEGMENT SALES	4,249	3,438	8,382	7,229
Office \| Operating Segments
Financial information of segments
SALES	179,270	160,877	364,626	328,600
INTERSEGMENT SALES	488	415	1,069	901
OPERATING PROFIT	13,597	9,099	30,193	16,345
Studio \| Operating Segments
Financial information of segments
SALES	88,650	77,863	160,156	148,057
INTERSEGMENT SALES	1,753	1,706	3,058	3,086
OPERATING PROFIT	14,067	12,079	23,110	21,031
Coverings \| Operating Segments
Financial information of segments
SALES	26,780	29,882	54,547	58,463
INTERSEGMENT SALES	2,008	1,317	4,255	3,242
OPERATING PROFIT	$ 5,810	$ 7,077	$ 12,020	$ 13,178

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

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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

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=26872669&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.

+ References

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- Definition

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.

+ References

No definition available.

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