|
LONG-TERM DEBT / INTEREST EXPENSE (Details) (USD $)
|
3 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
|
Mar. 31, 2015
|
Mar. 31, 2014
|
Dec. 31, 2014
|
Dec. 31, 2013
|
|
| Long-term Debt | ||||
| Interest expense, net | $ 11,515,000 | $ 11,531,000 | ||
| Revolving Credit Facility | ||||
| Long-term Debt | ||||
| Maximum borrowing capacity | 80,000,000.0 | |||
| Borrowing capacity increase limit | 130,000,000.0 | |||
| Commitment fee on undrawn portion of revolving credit facility (as a percent) | 0.50% | 0.50% | ||
| Letter Of Credit | ||||
| Long-term Debt | ||||
| Outstanding letters of credit | 1,100,000 | 1,100,000 | ||
| Outstanding letters of credit fee (as a percent) | 2.50% | 2.50% | ||
| Term Loan Facility | ||||
| Long-term Debt | ||||
| Maximum borrowing capacity | 1,400,000,000.0 | |||
| Borrowing capacity increase | $ 252,500,000.0 | |||
| Interest rate (as a percent) | 3.25% | 3.25% | ||