Note 11 - Held-to-maturity Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Sep. 30, 2017
Due in one year or less, amortized cost	$ 49,445	$ 59,113
Due in one year or less, fair market value	49,444	59,194
Due after one year through five years, amortized cost	82,066	60,908
Due after one year through five years, fair market value	81,689	61,113
Due after five years through ten years, amortized cost	0	0
Due after five years through ten years, fair market value	0	0
Total held to maturity securities, amortized cost	131,511	120,021
Total held to maturity securities, fair market value	131,133	120,307
Less current portion, amortized cost	49,445	59,113
Less current portion, fair market value	49,444	59,194
Long term held to maturity securities, amortized cost	82,066	60,908
Long term held to maturity securities, fair market value	$ 81,689	$ 61,113