LEGAL PROCEEDINGS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended	0 Months Ended	1 Months Ended			1 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 24, 2013 Potential violation of federal environmental laws item	Feb. 28, 2011 Potential violation of federal environmental laws item	Feb. 28, 2011 Putative class action item	Aug. 20, 2012 Putative class action	Mar. 30, 2011 Putative shareholder derivative lawsuits item	Sep. 30, 2013 Putative shareholder derivative lawsuits	Sep. 30, 2013 SEC Inquiry
LEGAL PROCEEDINGS
Number of alleged confidential informants					6
Settlement amount payable						$ 3,915		$ 495
Number of lawsuits							3
Number of lawsuits alleging violation of Section 14(a) of the Exchange Act in connection with proxy statement							1
Number of federal derivative lawsuits consolidated							2
Estimated loss due to legal matter									0
Number of facilities where search was conducted				1
Amount of fine	1,500	1,500	1,500
Number of installments over which fine is payable			3
Fine payable under each installment			$ 500
Period over which fine is payable			3 years