Quarterly report pursuant to Section 13 or 15(d)

Note 6 - Borrowings (Details Textual)

v3.8.0.1
Note 6 - Borrowings (Details Textual)
$ in Thousands
3 Months Ended
Oct. 21, 2014
USD ($)
Sep. 30, 2017
Dec. 31, 2017
USD ($)
Jun. 30, 2017
USD ($)
Debt Instrument, Term 5 years      
Debt Agreement, Maximum Borrowing Capacity $ 150,000      
Debt Issuance Costs, Net 1,500   $ 579
Letters of Credit Outstanding, Amount     200 100
Line of Credit Facility, Remaining Borrowing Capacity     $ 114,800 $ 114,900
Revolving Credit Facility [Member]        
Line of Credit Facility, Maximum Borrowing Capacity $ 115,000      
Debt Instrument, Covenant, Percentage of Total Revolving Credit 20.00%      
Revolving Credit Facility [Member] | Minimum [Member]        
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage 0.15%      
Revolving Credit Facility [Member] | Maximum [Member]        
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage 0.25%      
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member]        
Debt Instrument, Basis Spread on Variable Rate 1.00%      
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]        
Debt Instrument, Basis Spread on Variable Rate 1.50%      
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]        
Debt Instrument, Basis Spread on Variable Rate 1.75%      
Revolving Credit Facility [Member] | Federal Funds Effective Swap Rate [Member]        
Debt Instrument, Basis Spread on Variable Rate 0.50%      
Revolving Credit Facility [Member] | Additional Margin on Variable Rate Option [Member] | Minimum [Member]        
Debt Instrument, Basis Spread on Variable Rate 0.50%      
Revolving Credit Facility [Member] | Additional Margin on Variable Rate Option [Member] | Maximum [Member]        
Debt Instrument, Basis Spread on Variable Rate 0.75%      
Letter of Credit [Member] | Minimum [Member]        
Line of Credit Facility, Interest Rate During Period 1.50%      
Letter of Credit [Member] | Maximum [Member]        
Line of Credit Facility, Interest Rate During Period 1.75%      
Term Loan [Member]        
Long-term Debt $ 35,000      
Debt Instrument, Covenant, Minimum Fixed Charge Coverage Ratio 1.1      
Debt Covenant, Fixed Charge Coverage Ratio, Maximum Outstanding Term Loans $ 17,500      
Debt Instrument, Covenant, Minimum Fixed Charge Coverage Ratio for Covenant to Cease to Apply 1.25      
Debt Instrument, Covenant, Minimum Percentage of Total Revolving Credit to Avoid Triggering Fixed Charge Coverage Ratio Covenant 15.00%      
Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]        
Debt Instrument, Basis Spread on Variable Rate   1.75%    
Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]        
Debt Instrument, Basis Spread on Variable Rate   2.25%