Note 11 - Held to Maturity By Contractual Maturity (Details) - USD ($)	Mar. 25, 2017	Sep. 24, 2016
Due in one year or less, amortized cost	$ 37,176,000	$ 13,539,000
Due in one year or less, fair market value	37,182,000	13,552,000
Due after one year through five years, amortized cost	85,112,000	90,732,000
Due after one year through five years, fair market value	85,191,000	91,326,000
Due after five years through ten years, amortized cost
Due after five years through ten years, fair market value
Total held to maturity securities, amortized cost	122,288,000	104,271,000
Total held to maturity securities, fair market value	122,373,000	104,878,000
Marketable securities held to maturity	37,176,000	13,539,000
Less current portion, fair market value	37,182,000	13,552,000
Long term held to maturity securities, amortized cost	85,112,000	90,732,000
Long term held to maturity securities, fair market value	$ 85,191,000	$ 91,326,000