SEGMENT AND GEOGRAPHIC REGION INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012 item	Dec. 31, 2011	Dec. 31, 2010
SEGMENT AND GEOGRAPHIC REGION INFORMATION
Number of reportable segments									3
Net sales by product category
Net sales	$ 250,026	$ 219,794	$ 221,018	$ 196,662	$ 223,148	$ 239,543	$ 238,650	$ 220,858	$ 887,499	$ 922,200	$ 809,467
Office Systems
Net sales by product category
Net sales									424,405	440,395	353,536
Seating
Net sales by product category
Net sales									102,523	112,098	112,305
Files and Storage
Net sales by product category
Net sales									77,695	85,404	72,475
Studio
Net sales by product category
Net sales									147,550	152,724	151,917
Coverings
Net sales by product category
Net sales									106,628	105,344	95,246
Other
Net sales by product category
Net sales									$ 28,698	$ 26,235	$ 23,988