Quarterly report pursuant to Section 13 or 15(d)

Borrowings - Additional Information (Details)

v3.10.0.1
Borrowings - Additional Information (Details) - JP Morgan Chase Bank
 9 Months Ended
Sep. 29, 2018
USD ($)
Revolving Credit Facility  
Line of Credit Facility [Line Items]  
Maximum borrowing capacity (up to) $ 30,000,000
Revolving loan payable $ 0
Unused credit commitment fee (percent) 0.25%
Minimum availability required trigger amount (if less than) $ 3,600,000
Number of days below minimum excess availability that triggers cash dominion period 3 days
Number of consecutive days excess availability is above required amount 60 days
Event of default amount $ 0
Excess availability (greater than) 3,600,000
Minimum availability required under availability block $ 2,400,000
Minimum fixed charge ratio if less than minimum excess availability 1.0
Excess availability under credit facility $ 10,093,000
Principal payments due 0
Letter of Credit  
Line of Credit Facility [Line Items]  
Maximum borrowing capacity (up to) 15,246,000
Outstanding letters of credit amount $ 11,102,000
One-Month London Interbank Offered Rate (LIBOR) | Revolving Credit Facility  
Line of Credit Facility [Line Items]  
Applicable margin for LIBOR-based interest rate and applicable margin for alternate based rate (percent) 1.50%
Base Rate | Revolving Credit Facility  
Line of Credit Facility [Line Items]  
Applicable margin for LIBOR-based interest rate and applicable margin for alternate based rate (percent) 0.25%
Interest rate (percent) 5.25%
Prime based rate, principal amount $ 0
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility  
Line of Credit Facility [Line Items]  
Interest rate (percent) 3.75%
LIBOR based interest rate, principal amount $ 0