Note 2 - Acquisition (Details Textual) - USD ($)		3 Months Ended	6 Months Ended
	Apr. 03, 2017	Jul. 01, 2017	Sep. 30, 2017	Oct. 01, 2016	Apr. 02, 2017	Apr. 30, 2014
Business Combination, Bargain Purchase, Gain Recognized, Amount			$ 1,096,000
Truitt Bros. Inc. [Member]
Business Acquisition, Percentage of Voting Interests Acquired	50.00%
Business Combination, Bargain Purchase, Gain Recognized, Amount	$ 1,096,000	$ 1,096,000	1,096,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain		562,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement of Inventory, Impact on Cost of Goods Sold		$ 542,000
Business Combination, Consideration Transferred	14,420,000		$ 14,420,000
Cash Acquired from Acquisition	3,030,000
Equity Method Investments	34,872,000				$ 17,422,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt	3,608,000
Business Combination, Consideration Transferred, Including Equity Interest in Acquiree Held Prior to Combination	$ 31,842,000
Truitt Bros. Inc. Investment [Member]
Equity Method Investment, Ownership Percentage						50.00%
Equity Method Investment, Aggregate Cost						$ 16,242,000
Purchase Agreement, Additional Percentage of Voting Interests Acquirable						50.00%