Investments (Details Textual) - USD ($)	3 Months Ended			6 Months Ended
	Sep. 26, 2015	Jun. 27, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014	Mar. 28, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ 826,000			$ 826,000		$ 136,000
Investments (Textual) [Abstract]
Value of investments to be other-than-temporarily impaired		$ 0
Gross gains realized	51,000		$ 123,000	231,000	$ 426,000
Gross losses realized	(66,000)		$ (11,000)	(112,000)	$ (79,000)
Common stock of industrial and other companies [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	5,600,000			5,600,000		5,400,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(753,000)			(753,000)		(85,000)
Common stock of bank trust, insurance, and public utility companies [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	100,000			100,000		100,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	$ (3,000)			$ (3,000)		$ (3,000)