8. FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
First Lien Term Loan
FAIR VALUE MEASUREMENTS
Term loans face value	$ 389,367	$ 399,750
2015 Incremental First
FAIR VALUE MEASUREMENTS
Term loans face value	74,013
Second Lien Term Loans
FAIR VALUE MEASUREMENTS
Term loans face value	180,000	180,000
Level 1 | First Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0	0
Level 1 | 2015 Incremental First
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0
Level 1 | Second Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0	0
Level 2 | First Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	388,880	394,753
Level 2 | 2015 Incremental First
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	73,920
Level 2 | Second Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	176,400	178,200
Level 3 | First Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0	0
Level 3 | 2015 Incremental First
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0
Level 3 | Second Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	0	0
Total Fair Value | First Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	388,880	394,753
Total Fair Value | 2015 Incremental First
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	73,920
Total Fair Value | Second Lien Term Loans
FAIR VALUE MEASUREMENTS
Long-Term Debt fair value	$ 176,400	$ 178,200