Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments (Details)

v2.4.0.8
Fair Value of Financial Instruments (Details) (USD $)
Sep. 27, 2014
Dec. 28, 2013
Assets    
Assets measured at fair value, Adjusted cost $ 55,838,000  
Asset measured at, fair value 55,232,000  
Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 55,838,000 38,917,000
Assets measured at fair value, Unrealized gains 179,000 284,000
Assets measured at fair value, Unrealized losses (785,000) (472,000)
Asset measured at, fair value 55,232,000 38,729,000
Level 1 [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 12,091,000 5,914,000
Assets measured at fair value, Unrealized gains 158,000 156,000
Assets measured at fair value, Unrealized losses (220,000) (65,000)
Asset measured at, fair value 12,029,000 6,005,000
Liabilities    
Liabilities measured at fair value, Adjusted cost   38,000
Liabilities measured at fair value, Unrealized gains 0 0
Liabilities measured at fair value, Unrealized losses 0 0
Liabilities measured at fair value 65,000 38,000
Convertible Debt, Fair Value Disclosures 65,000  
Level 1 [Member] | Phantom stock units [Member] | Recurring [Member]
    
Liabilities    
Liabilities measured at fair value, Adjusted cost 65,000 38,000
Liabilities measured at fair value, Unrealized gains 0 0
Liabilities measured at fair value, Unrealized losses 0 0
Liabilities measured at fair value 65,000 38,000
Level 1 [Member] | Equity securities [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 1,827,000 2,049,000
Assets measured at fair value, Unrealized gains 124,000 137,000
Assets measured at fair value, Unrealized losses (178,000) (64,000)
Asset measured at, fair value 1,773,000 2,122,000
Level 1 [Member] | Mutual funds [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 10,264,000 3,865,000
Assets measured at fair value, Unrealized gains 34,000 19,000
Assets measured at fair value, Unrealized losses (42,000) (1,000)
Asset measured at, fair value 10,256,000 3,883,000
Level 2 [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 43,747,000 33,003,000
Assets measured at fair value, Unrealized gains 21,000 128,000
Assets measured at fair value, Unrealized losses (565,000) (407,000)
Asset measured at, fair value 43,203,000 32,724,000
Level 2 [Member] | Corporate fixed income [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 39,019,000 25,240,000
Assets measured at fair value, Unrealized gains 21,000 126,000
Assets measured at fair value, Unrealized losses (469,000) (250,000)
Asset measured at, fair value 38,571,000 25,116,000
Level 2 [Member] | Municipal bonds [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 3,790,000 2,775,000
Assets measured at fair value, Unrealized gains 0 1,000
Assets measured at fair value, Unrealized losses (29,000) (28,000)
Asset measured at, fair value 3,761,000 2,748,000
Level 2 [Member] | Certificates of deposit [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost   4,014,000
Assets measured at fair value, Unrealized gains   1,000
Assets measured at fair value, Unrealized losses   0
Asset measured at, fair value   4,015,000
Level 2 [Member] | Asset backed securities [Member] | Recurring [Member]
    
Assets    
Assets measured at fair value, Adjusted cost 887,000 974,000
Assets measured at fair value, Unrealized gains 0 0
Assets measured at fair value, Unrealized losses (67,000) (129,000)
Asset measured at, fair value $ 820,000 $ 845,000