RESTRUCTURING (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended				45 Months Ended
	Mar. 31, 2015 sqft item	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2015	Sep. 30, 2012
RESTRUCTURING
Restructuring charges			$ 2,153	$ 5,550	$ 5,092	$ 874	$ 13,669
Accelerated depreciation				898	819		1,717
Severance				435		430	865
Iimpairment charges				2,365			2,365
Percentage of facility footprint planned to be reduced through the sale and/or closure	40.00%
Area of facilities planned to be reduced through the sale and/or closure (in square feet)	600,000
Number of facilities for which agreement has been reached to close or reduce leased presence	6
Area of facilities for which agreement has been reached to close or reduce leased presence	400,000
Number of remaining properties vacated and marketed for sale	2
Liability associated with environmental remediation costs	513						513	352
Addition in liability associated with environmental remediation costs		258
Restructuring Reserve, Settled without Cash							4,800
Capital expenditures
RESTRUCTURING
Exit costs			674	2,352	2,596	5	5,627
Moving and other exit-related costs
RESTRUCTURING
Exit costs			1,479	3,085	1,677	439	6,680
Brandon Facility
RESTRUCTURING
Gain on sale of Brandon, SD Facility				$ (3,585)			$ (3,585)