Note 5 - Derivative Financial Instruments - Derivatives Instruments, Statements of Financial Performance and Financial Position (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 27, 2019	Jul. 28, 2018
(Loss) gain before income taxes	$ (1,423)	$ 6,347
Less income tax (benefit) provision	(340)	1,518
Net	(1,083)	4,829
(Loss) gain before income taxes	(1,444)	8,934
Less income tax (benefit) provision	(345)	2,064
Net	(1,099)	6,870
Net change to AOCI	$ 16	$ (2,041)

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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