Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt (Narrative) (Details)

v3.8.0.1
Long-Term Debt (Narrative) (Details)
$ in Thousands
 9 Months Ended
Sep. 30, 2017
USD ($)
Line Of Credit Facility And Long Term Debt [Line Items]  
Credit facility maximum borrowing capacity $ 40,000
Revolving Credit Facility [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Line of credit facility, amount outstanding 27,353
Third Amendment to Second Amended and Restated Loan Agreement [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Credit facility maximum borrowing capacity 40,000
Credit facility quarterly reductions in borrowing capacity 1,250
Credit facility maximum borrowing capacity after quarterly reductions 20,000
Credit facility temporary increase in borrowing capacity 20,000
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases $ 30,000
Basis spread on variable rate 4.00%
Third Amendment to Second Amended and Restated Loan Agreement Option 1 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Basis spread on variable rate 3.00%
Third Amendment to Second Amended and Restated Loan Agreement Option 2 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Basis spread on variable rate 2.00%
Third Amendment to Second Amended and Restated Loan Agreement Option 3 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Basis spread on variable rate 1.50%
Minimum [Member] | Third Amendment to Second Amended and Restated Loan Agreement [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 2.75
Minimum [Member] | Third Amendment to Second Amended and Restated Loan Agreement Option 1 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 2.00
Minimum [Member] | Third Amendment to Second Amended and Restated Loan Agreement Option 2 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 1.00
Maximum [Member] | Third Amendment to Second Amended and Restated Loan Agreement Option 1 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 2.75
Maximum [Member] | Third Amendment to Second Amended and Restated Loan Agreement Option 2 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 2.00
Maximum [Member] | Third Amendment to Second Amended and Restated Loan Agreement Option 3 [Member]  
Line Of Credit Facility And Long Term Debt [Line Items]  
Debt to EBITDA ratio used in margin calculation 1.00