Note 11 (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 30, 2017	Dec. 24, 2016	Dec. 30, 2017	Sep. 30, 2017
Held-to-maturity Securities	$ 131,511,000		$ 131,511,000	$ 120,021,000
Proceeds from Sale and Maturity of Marketable Securities	19,096,000	$ 475,000	19,096,000
Marketable Securities, Gain (Loss)	7,558	$ 0
Corporate Bond Securities [Member]
Held-to-maturity Securities	$ 123,000,000		$ 123,000,000
Investment Securities Maturity Term	3 years