Quarterly report pursuant to Section 13 or 15(d)

DEBT - Narrative (Details)

v3.6.0.2
DEBT - Narrative (Details) - USD ($)
 1 Months Ended 3 Months Ended 9 Months Ended
Oct. 21, 2016
Nov. 30, 2016
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Mar. 31, 2016
Debt Instrument [Line Items]              
Gain (loss) on debt extinguishment     $ (48,000) $ (394,000) $ (48,000) $ (394,000)  
Debt issuance costs $ 4,700,000            
Refundable deposits 1,000,000            
Outstanding letters of credit     72,239,000   72,239,000   $ 62,709,000
Long-term debt     76,000,000   76,000,000    
Credit agreement              
Debt Instrument [Line Items]              
Reserve requirement     20,000,000   20,000,000    
Debt issuance costs 3,100,000            
Debt discount 1,000,000            
Loan commitment fees 600,000            
Credit agreement | Letter of credit              
Debt Instrument [Line Items]              
Outstanding letters of credit     1,000,000   1,000,000    
Credit agreement with Wells Fargo              
Debt Instrument [Line Items]              
Repayments of outstanding balance 60,300,000            
Credit agreement with Wells Fargo | Convertible subordinated debt              
Debt Instrument [Line Items]              
Gain (loss) on debt extinguishment (100,000)            
Credit agreement with Wells Fargo | Credit agreement              
Debt Instrument [Line Items]              
Long-term debt     0   0   62,709,000
Term loan agreement              
Debt Instrument [Line Items]              
Debt issuance costs 1,200,000            
Debt discount 1,000,000            
Long-term debt     50,000,000   50,000,000    
DDTL     20,000,000   $ 20,000,000    
Interest rate during the period (percent)         8.50%    
Term loan agreement | Federal funds rate              
Debt Instrument [Line Items]              
Variable interest rate         0.50%    
Term loan agreement | One month LIBOR              
Debt Instrument [Line Items]              
Variable interest rate         1.00%    
Term loan agreement | Base rate              
Debt Instrument [Line Items]              
Variable interest rate         3.00%    
Term loan agreement | Minimum | Prime rate quoted by the Wall Street Journal              
Debt Instrument [Line Items]              
Variable interest rate         6.00%    
Term loan agreement | Minimum | LIBOR rate plus senior net leverage ratio              
Debt Instrument [Line Items]              
Variable interest rate         7.00%    
Term loan agreement | Maximum | Prime rate quoted by the Wall Street Journal              
Debt Instrument [Line Items]              
Variable interest rate         7.25%    
Term loan agreement | Maximum | LIBOR rate plus senior net leverage ratio              
Debt Instrument [Line Items]              
Variable interest rate         8.25%    
Term loan agreement | Credit agreement              
Debt Instrument [Line Items]              
Debt Instrument, Face Amount 50,000,000.0            
Revolving Credit Agreement with PNC              
Debt Instrument [Line Items]              
Debt issuance costs 1,900,000            
Loan commitment fee 600,000            
Commitment fee percentage on unused capacity (percent)         0.375%    
Long-term debt     26,000,000   $ 26,000,000    
Revolving Credit Agreement with PNC | Federal funds rate              
Debt Instrument [Line Items]              
Variable interest rate         0.50%    
Revolving Credit Agreement with PNC | One month LIBOR              
Debt Instrument [Line Items]              
Variable interest rate         1.00%    
Revolving Credit Agreement with PNC | Minimum | One Month LIBOR margin              
Debt Instrument [Line Items]              
Variable interest rate         1.50%    
Revolving Credit Agreement with PNC | Maximum | One Month LIBOR margin              
Debt Instrument [Line Items]              
Variable interest rate         2.50%    
Revolving Credit Agreement with PNC | Credit agreement              
Debt Instrument [Line Items]              
Debt Instrument, Face Amount 26,000,000.0            
Available uncommitted accordion         $ 20,000,000    
Revolving Credit Agreement with PNC | Credit agreement | Revolving credit agreement              
Debt Instrument [Line Items]              
Restricted reserve funded amount 10,000,000            
Reserve requirement $ 20,000,000.0            
Borrowing capacity     80,000,000   80,000,000    
Long-term debt     $ 26,000,000   $ 26,000,000   $ 0
Line of credit at an interest rate     3.31%   3.31%    
4.50% convertible subordinated notes              
Debt Instrument [Line Items]              
Long-term debt     $ 64,590,000   $ 64,590,000    
Stated interest rate     4.50%   4.50%    
Quarterly repayment of original principal balance (percent)     1.25%   1.25%    
4.50% convertible subordinated notes | Convertible subordinated debt              
Debt Instrument [Line Items]              
Gain (loss) on debt extinguishment   $ 100,000          
Stated interest rate   4.50%          
Extinguishment of debt   $ 5,400,000          
Cash paid for extinguishment of debt   $ 5,300,000