SEGMENT AND GEOGRAPHIC REGION INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Financial information of segments
NET SALES	$ 286,453	$ 268,297	$ 265,943	$ 229,601	$ 230,456	$ 216,898	$ 214,312	$ 200,586	$ 1,050,294		$ 862,252		$ 898,496
OPERATING PROFIT		23,315	22,238	11,284	1,806	16,854	12,605	10,148	76,843		41,413		91,472
Liability loss related to curtailment									6,509		0		0
Restructuring and other charges	700		203	592	5,104		0	0	1,532		5,104		0
Intangible asset impairment charge					8,900				0		8,900		0
Operating Segments
Financial information of segments
NET SALES									1,050,294		862,252		898,496
INTERSEGMENT SALES									19,270	[1]	18,014	[1]	16,617	[1]
DEPRECIATION AND AMORTIZATION									20,042		16,361		16,547
OPERATING PROFIT									84,884		55,417		91,472
CAPITAL EXPENDITURES, NET									41,586		29,064		16,545
Office | Operating Segments
Financial information of segments
NET SALES									656,228		599,131		644,318
INTERSEGMENT SALES									2,776	[1]	1,698	[1]	1,727	[1]
DEPRECIATION AND AMORTIZATION									13,747		13,116		13,409
OPERATING PROFIT									29,412		16,111		52,210
Liability loss related to curtailment									5,300
CAPITAL EXPENDITURES, NET									33,226		25,300		14,251
Studio | Operating Segments
Financial information of segments
NET SALES									279,167		154,083		147,550
INTERSEGMENT SALES									5,918	[1]	6,594	[1]	5,299	[1]
DEPRECIATION AND AMORTIZATION									5,313		2,085		2,055
OPERATING PROFIT									33,451		18,310		21,786
Liability loss related to curtailment									800
CAPITAL EXPENDITURES, NET									8,075		3,063		1,871
Coverings | Operating Segments
Financial information of segments
NET SALES									114,899		109,038		106,628
INTERSEGMENT SALES									10,576	[1]	9,722	[1]	9,591	[1]
DEPRECIATION AND AMORTIZATION									982		1,160		1,083
OPERATING PROFIT									22,021		20,996		17,476
Liability loss related to curtailment									400
CAPITAL EXPENDITURES, NET									$ 285		$ 701		$ 423

[1] Intersegment sales are presented on a cost-plus basis which takes into consideration the effect of transfer prices between legal entities.