ACCRUED EXPENSES AND NON-CURRENT LIABILITIES (Non-current Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Other Long Term Liabilities [Line Items]
Long-term accrued interest	$ 1,733	$ 242
Asset retirement obligation	980	926
Deferred rent	621	717
Long-term liabilities related to the Cooperative Endeavor Agreement with the State of Louisiana	2,244	2,445
Long-term portion of liability for contingent consideration	1,832	2,944
Uncertain income tax positions	5,728	5,408
Other non-current liabilities	17,357	17,444
Foreign Tax [Member]
Other Long Term Liabilities [Line Items]
Foreign tax contingencies	$ 4,219	$ 4,762