INVESTMENTS IN SECURITIES (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014	Dec. 28, 2014
Schedule of Available-for-sale Securities [Line Items]
Gross realized gains, available-for-sale securities	$ 193,200	$ 51,900	$ 390,400	$ 310,000
Gross realized losses, available-for-sale securities	5,400	$ 7,700	25,400	$ 8,100
Fixed income securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income securities, Amortized Cost	262,738,000		262,738,000		$ 204,286,000
Fixed income securities, Fair Value	262,738,000		262,738,000		204,286,000
Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed income securities, Amortized Cost	51,000		51,000		80,000
Fixed income securities, Fair Value	$ 51,000		$ 51,000		$ 80,000