Quarterly report pursuant to Section 13 or 15(d)

SEGMENT INFORMATION (Details)

v3.4.0.3
SEGMENT INFORMATION (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Dec. 31, 2015
Segment Reporting Information [Line Items]      
Net revenues $ 52,200 $ 55,143  
Operating profit before depreciation and amortization 8,541 11,974  
Operating profit (loss) 6,145 9,733  
Depreciation and amortization 2,396 2,241  
Capital expenditures 7,602 7,743  
Goodwill and intangible assets, net 45,877   $ 46,347
Total assets 262,729   257,791
Product Sales [Member]      
Segment Reporting Information [Line Items]      
Net revenues 47,181 50,541  
Processing Fees [Member]      
Segment Reporting Information [Line Items]      
Net revenues 5,019 4,602  
Eliminations [Member]      
Segment Reporting Information [Line Items]      
Goodwill and intangible assets, net 0   0
Total assets (126,073)   (122,371)
Corporate [Member]      
Segment Reporting Information [Line Items]      
Net revenues 0 0  
Operating profit before depreciation and amortization (1,933) (1,812)  
Operating profit (loss) (1,941) (1,812)  
Depreciation and amortization 8 0  
Capital expenditures 0 0  
Goodwill and intangible assets, net 0   0
Total assets 101,401   98,728
Corporate [Member] | Product Sales [Member]      
Segment Reporting Information [Line Items]      
Net revenues 0 0  
Corporate [Member] | Processing Fees [Member]      
Segment Reporting Information [Line Items]      
Net revenues 0 0  
Petrochemical [Member] | Operating Segments [Member]      
Segment Reporting Information [Line Items]      
Net revenues 44,065 48,707  
Operating profit before depreciation and amortization 8,412 11,712  
Operating profit (loss) 7,075 10,617  
Depreciation and amortization 1,337 1,095  
Capital expenditures 5,662 6,815  
Goodwill and intangible assets, net 0   0
Total assets 199,696   195,358
Petrochemical [Member] | Operating Segments [Member] | Product Sales [Member]      
Segment Reporting Information [Line Items]      
Net revenues 42,624 47,183  
Petrochemical [Member] | Operating Segments [Member] | Processing Fees [Member]      
Segment Reporting Information [Line Items]      
Net revenues 1,441 1,524  
Specialty Wax [Member] | Operating Segments [Member]      
Segment Reporting Information [Line Items]      
Net revenues 8,135 6,436  
Operating profit before depreciation and amortization 2,062 2,074  
Operating profit (loss) 1,011 928  
Depreciation and amortization 1,051 1,146  
Capital expenditures 1,940 928  
Goodwill and intangible assets, net 45,877   46,347
Total assets 87,705   $ 86,076
Specialty Wax [Member] | Operating Segments [Member] | Product Sales [Member]      
Segment Reporting Information [Line Items]      
Net revenues 4,557 3,358  
Specialty Wax [Member] | Operating Segments [Member] | Processing Fees [Member]      
Segment Reporting Information [Line Items]      
Net revenues $ 3,578 $ 3,078