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Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
Intangibles (Details) - USD ($) $ in Thousands	Jul. 27, 2019	Jul. 28, 2018	Apr. 30, 2019
Intangibles
Intangibles, gross	$ 18,590		$ 1,770
Less accumulated amortization	(1,863)		(1,311)
Intangibles, net	$ 16,727		$ 459
Weighted average amortization period	5 years		1 year
Amortization expense	$ 552	$ 69
Technology
Intangibles
Intangibles, gross	14,950
In process research and development
Intangibles
Intangibles, gross	1,370
Licenses
Intangibles
Intangibles, gross	1,006		$ 1,006
Customer relationships
Intangibles
Intangibles, gross	873		733
Non-compete agreements
Intangibles
Intangibles, gross	320
Trademarks and tradenames
Intangibles
Intangibles, gross	68		28
Other
Intangibles
Intangibles, gross	$ 3		$ 3