Income Taxes Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 28, 2017	Apr. 29, 2016	Apr. 24, 2015
Current:
Federal	$ (3,647)	$ 3,714	$ (5,679)
State	(173)	873	(779)
Total current	(3,820)	4,587	(6,458)
Deferred:
Federal	8,364	1,704	(1,922)
State	(670)	148	(246)
Total deferred	7,694	1,852	(2,168)
Total tax provision (benefit)	$ 3,874	$ 6,439	$ (8,626)

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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