Note 5 - Derivative Financial Instruments - Derivatives Instruments, Statements of Financial Performance and Financial Position (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Oct. 26, 2019	Oct. 27, 2018	Oct. 26, 2019	Oct. 27, 2018
(Loss) gain before income taxes	$ (619)	$ 1,076	$ (2,043)	$ 7,424
Less income tax (benefit) provision	(148)	257	(489)	1,776
Net	(471)	819	(1,554)	5,648
(Loss) gain before income taxes	(1,170)	4,596	(2,614)	13,530
Less income tax (benefit) provision	(280)	1,062	(625)	3,126
Net	(890)	3,534	(1,989)	10,404
Net change to AOCI	$ 419	$ (2,715)	$ 435	$ (4,756)

Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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