SEGMENT INFORMATION Segment Information with Corporate Costs Excluded (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Financial information of segments
SALES	$ 323,351	$ 268,694	$ 619,910	$ 525,514
OPERATING PROFIT	24,812	19,832	47,272	40,468
Operating Segments
Financial information of segments
SALES	323,351	268,694	619,910	525,514
INTERSEGMENT SALES	3,547	2,592	6,413	5,915
Corporate
Financial information of segments
OPERATING PROFIT	(6,469)	(5,564)	(13,051)	(12,167)
Acquisition costs	500		1,500
Office
Financial information of segments
Restructuring charges	800	2,200	1,400	2,200
Office \| Operating Segments
Financial information of segments
SALES	190,747	162,599	372,365	320,597
INTERSEGMENT SALES	497	450	1,009	724
OPERATING PROFIT	10,316	4,812	19,182	13,639
Lifestyle \| Operating Segments
Financial information of segments
SALES	132,604	106,095	247,545	204,917
INTERSEGMENT SALES	3,050	2,142	5,404	5,191
OPERATING PROFIT	$ 20,965	$ 20,584	$ 41,141	$ 38,996

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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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)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-03.1)
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