LONG-TERM DEBT OBLIGATIONS, Convertible Senior Notes (Details) (4.00% Convertible Senior Notes, USD $)
 0 Months Ended 3 Months Ended
Jul. 25, 2012
Jun. 25, 2012
Mar. 31, 2015
4.00% Convertible Senior Notes
      
Debt Instrument [Line Items]      
Senior Notes   $ 105,000,000.0 $ 105,000,000
Debt Instrument, Interest Rate, Stated Percentage   4.00%  
Debt issuance costs   3,900,000  
Net proceeds from issuance of 4.00% convertible senior notes   101,100,000  
Amortization period for debt issuance cost related to convertible notes   7 years  
Debt Instrument, Convertible, Shares per $1,000 principal amount of 4.00% Convertible Senior Notes 170.0319    
Aggregate principal amount of senior convertible notes repurchased   1,000  
Maximum number of shares upon conversion of the 4.00% Notes   17,857,143  
Debt Instrument, Convertible, Conversion Price   $ 5.88  
Percentage of common stock above conversion price (in hundredths)   130.00%  
Number of consecutive trading days within measurement period   20 days  
Number of consecutive trading days on which trading price is examined for triggering of conversion   30 days  
Number of trading days to trigger measurement period within date company provides notice of redemption   5 days  
Percentage of Principal Amount That The Redemption Price Will Be Equal To   100.00%  
Debt Instrument, 4.00% Convertible, Interest Expense     $ 1,200,000