Annual report pursuant to Section 13 and 15(d)

Long-Term Debt (Details Textual)

v3.6.0.2
Long-Term Debt (Details Textual)
12 Months Ended
Nov. 22, 2016
USD ($)
Aug. 01, 2011
USD ($)
CreditFacility
Dec. 31, 2016
USD ($)
CreditFacility
Jan. 02, 2016
USD ($)
Debt Instrument [Line Items]        
Revolving line of credit     $ 140,000,000 $ 0
Interest expense recognized     483,000  
Other Assets [Member]        
Debt Instrument [Line Items]        
Debt issuance costs     1,959,000  
2016 A&R Credit Agreement [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity $ 300,000,000      
Expiration date Nov. 22, 2021      
Accordion feature to increase maximum capacity $ 100,000,000      
Interest coverage ratio 3.0      
Leverage ratio thereafter 3.5      
2016 A&R Credit Agreement [Member] | Revolving Credit Facility [Member] | PNC Bank National Association [Member]        
Debt Instrument [Line Items]        
Revolving line of credit     140,000,000  
Additional credit available subject to pro forma compliance with debt covenant     $ 160,000,000  
Interest rate in effect     2.77%  
2016 A&R Credit Agreement [Member] | Swing Loans [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity $ 20,000,000      
2016 A&R Credit Agreement [Member] | Letter of Credit [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity $ 10,000,000      
2016 A&R Credit Agreement [Member] | Minimum [Member] | Euro Rate [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Variable interest rate (percent) 1.25%      
2016 A&R Credit Agreement [Member] | Minimum [Member] | Base Rate [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Variable interest rate (percent) 0.25%      
2016 A&R Credit Agreement [Member] | Maximum [Member] | Euro Rate [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Variable interest rate (percent) 2.25%      
2016 A&R Credit Agreement [Member] | Maximum [Member] | Base Rate [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Variable interest rate (percent) 1.25%      
Fifth Third Agreement [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity   $ 50,000,000    
Effective date   Aug. 01, 2011    
Number Of Credit Facilities | CreditFacility   3 0  
Line of credit balance     $ 0 $ 0
Fifth Third Agreement [Member] | Revolving Credit Facility [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity     35,000,000  
Fifth Third Agreement [Member] | Unsecured Revolving Line of Credit [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity     15,000,000  
Fifth Third Agreement [Member] | Construction and Term Loan [Member]        
Debt Instrument [Line Items]        
Credit facilities, maximum capacity     $ 15,000,000