Note 5 - Derivative Financial Instruments - Derivatives Instruments, Statements of Financial Performance and Financial Position (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 25, 2020	Jan. 26, 2019	Jan. 25, 2020	Jan. 26, 2019
(Loss) gain before income taxes	$ (581)	$ (1,937)	$ (2,623)	$ 5,487
Less income tax (benefit) provision	(139)	(463)	(628)	1,313
Net	(442)	(1,474)	(1,995)	4,174
(Loss) gain before income taxes	(742)	(305)	(3,356)	13,225
Less income tax (benefit) provision	(177)	(73)	(803)	3,053
Net	(565)	(232)	(2,553)	10,172
Net change to AOCI	$ 123	$ (1,242)	$ 558	$ (5,998)

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 after 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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