DEBT (Details) - USD ($) | Jun. 28, 2013 | Dec. 19, 2012 | Apr. 01, 2017 | Dec. 31, 2016 | Aug. 09, 2013 |
Amended And Restated Credit Agreement | Wells Fargo | | | | | |
Debt. | | | | | |
Maximum borrowing capacity | | $ 45,000,000 | | | |
Term of credit agreement | | 5 years | | | |
Unused credit capacity under the agreement | | | $ 35,000,000 | | |
Amended And Restated Credit Agreement | Wells Fargo | Prime Rate [Member] | | | | | |
Debt. | | | | | |
Effective interest rate (as a percent) | | | 3.06% | 3.05% | |
Variable interest rate basis | | | prime rate | | |
Amended And Restated Credit Agreement | Wells Fargo | London Interbank Offered Rate L I B O R [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | LIBOR | | |
Revolving Credit Facility | Wells Fargo | | | | | |
Debt. | | | | | |
Maximum borrowing capacity | | | $ 35,000,000 | | |
Borrowings outstanding under credit facility | | | $ 0 | $ 0 | |
Revolving Credit Facility | Wells Fargo | Prime Rate [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | prime rate | | |
Revolving Credit Facility | Wells Fargo | London Interbank Offered Rate L I B O R [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | LIBOR | | |
Revolving Credit Facility | Wells Fargo | Debt Instrument Variable Rate Federal Funds Rate [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | federal funds rate | | |
Basis spread on variable interest rate basis (as a percent) | | | 0.50% | | |
Revolving Credit Facility | Wells Fargo | Minimum | | | | | |
Debt. | | | | | |
Quarterly commitment fee (as a percent) | | | 0.20% | | |
Revolving Credit Facility | Wells Fargo | Minimum | London Interbank Offered Rate L I B O R [Member] | | | | | |
Debt. | | | | | |
Basis spread on variable interest rate basis (as a percent) | | | 1.50% | | |
Revolving Credit Facility | Wells Fargo | Minimum | Base Rate [Member] | | | | | |
Debt. | | | | | |
Basis spread on variable interest rate basis (as a percent) | | | 0.50% | | |
Revolving Credit Facility | Wells Fargo | Maximum | | | | | |
Debt. | | | | | |
Quarterly commitment fee (as a percent) | | | 0.50% | | |
Revolving Credit Facility | Wells Fargo | Maximum | London Interbank Offered Rate L I B O R [Member] | | | | | |
Debt. | | | | | |
Basis spread on variable interest rate basis (as a percent) | | | 2.50% | | |
Revolving Credit Facility | Wells Fargo | Maximum | Base Rate [Member] | | | | | |
Debt. | | | | | |
Basis spread on variable interest rate basis (as a percent) | | | 1.50% | | |
Secured Debt [Member] | Interest Rate Swap | Cash Flow Hedging | | | | | |
Debt. | | | | | |
Notional amount | | | | | $ 5,000,000 |
Fixed interest rate (as a percent) | | | | | 3.10% |
Secured Debt [Member] | Wells Fargo | | | | | |
Debt. | | | | | |
Maximum borrowing capacity | | | $ 10,000,000 | | |
Principal amount payable in quarterly installments | $ 166,667 | | | | |
Term loan facility | | | $ 7,300,000 | 7,500,000 | |
Secured Debt [Member] | Wells Fargo | Prime Rate [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | prime rate | | |
Secured Debt [Member] | Wells Fargo | London Interbank Offered Rate L I B O R [Member] | | | | | |
Debt. | | | | | |
Variable interest rate basis | | | LIBOR | | |
Letter Of Credit | | | | | |
Debt. | | | | | |
Aggregate outstanding amount | | | $ 1,900,000 | $ 1,900,000 | |