Schedule I - Condensed Financial Information of Registrant (Condensed Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jan. 25, 2020	Oct. 26, 2019	Jul. 27, 2019	Apr. 27, 2019	Jan. 26, 2019	Oct. 27, 2018	Jul. 28, 2018	Apr. 28, 2018	Jan. 25, 2020	Jan. 26, 2019	Jan. 27, 2018
Net sales	$ 397,716	$ 318,734	$ 342,321	$ 306,264	$ 354,065	$ 267,180	$ 288,493	$ 256,161	$ 1,365,035	$ 1,165,899	$ 950,528
Cost of sales									977,083	780,048	643,570
Gross profit	114,091	85,413	100,398	88,051	117,239	85,991	97,378	85,244	387,952	385,851	306,958
Operating expenses
Selling, general and administrative expenses									302,300	303,453	211,057
Depreciation and amortization									7,626	6,363	6,118
Operating (loss) income	(209,149)	1,986	21,813	25,889	44,568	19,096	(11,828)	24,200	(159,462)	76,035	87,361
Interest expense, net									31,801	27,056	21,704
Income tax provision (benefit)									23,172	(17)	33,845
Net (loss) income	$ (224,053)	$ (14,647)	$ 10,382	$ 13,883	$ 29,613	$ 11,090	$ (10,068)	$ 18,361	(214,435)	48,996	31,812
Parent company
Operating expenses
Net (loss) income from subsidiaries									(214,435)	48,996	31,812
Net (loss) income									$ (214,435)	$ 48,996	$ 31,812

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