RESTRUCTURING CHARGES - Summary of Changes in Restructuring Liability (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restructuring Reserve [Roll Forward]
Balance, as of December 31, 2014			$ 1,062
Restructuring charges	$ 441	$ 0	441	$ 795
Payments			(964)
Balance, as of September 30, 2015	539		539
Office Segment
Restructuring Reserve [Roll Forward]
Balance, as of December 31, 2014			1,046
Restructuring charges			0	$ 800
Payments			(725)
Balance, as of September 30, 2015	321		321
Studio Segment
Restructuring Reserve [Roll Forward]
Balance, as of December 31, 2014			0
Restructuring charges			441
Payments			(223)
Balance, as of September 30, 2015	218		218
Coverings Segment
Restructuring Reserve [Roll Forward]
Balance, as of December 31, 2014			16
Restructuring charges			0
Payments			(16)
Balance, as of September 30, 2015	$ 0		$ 0