Annual report pursuant to Section 13 and 15(d)

Debt and Capital Lease Obligations (Details)

v3.6.0.2
Debt and Capital Lease Obligations (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Feb. 04, 2015
Line of Credit Facility [Line Items]        
Credit facility term (in years)       5
Senior credit facility amount       $ 275,000
Base reference rate of credit facilities LIBOR      
Utilized for outstanding letters of credit $ 7,514      
Available borrowing capacity 142,486      
Proceeds from Issuance of Long-term Debt $ 0 $ 125,000 $ 0  
Revolving Credit Facility [Member]        
Line of Credit Facility [Line Items]        
Senior credit facility amount       $ 150,000
Basis spread on variable rate minimum (in hundredths)       0.30%
Basis spread on variable rate maximum (in hundredths)       0.80%
Term loan [Member]        
Line of Credit Facility [Line Items]        
Senior credit facility amount       $ 125,000
Basis spread on variable rate minimum (in hundredths)       0.10%
Basis spread on variable rate maximum (in hundredths)       0.60%
Proceeds from Issuance of Long-term Debt   $ 125,000    
Term Loan, Quarterly Payment Percentage 11.10%      
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate 2.00%      
Other Long-term Debt $ 27,788      
Letter of Credit [Member]        
Line of Credit Facility [Line Items]        
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases       $ 25,000
Swing line loan [Member]        
Line of Credit Facility [Line Items]        
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases       $ 15,000
Federal funds [Member]        
Line of Credit Facility [Line Items]        
Debt Instrument, Basis Spread on Variable Rate 0.50%      
LIBOR [Member]        
Line of Credit Facility [Line Items]        
Debt Instrument, Basis Spread on Variable Rate 1.00%