Amortizable Intangible Assets and Unamortizable Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jul. 28, 2018	Jul. 29, 2017		Apr. 28, 2018
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	$ 17,278	$ 25,498
Accumulated Amortization	(17,033)	(24,782)
Total	245	716
Unamortizable intangible assets	309,294	309,294	[1]
Total amortizable and unamortizable, intangible assets	309,539	310,010		$ 309,649
Trade name
Intangible Assets by Major Class [Line Items]
Unamortizable intangible assets	293,400	293,400	[1]
Publishing contracts
Intangible Assets by Major Class [Line Items]
Unamortizable intangible assets	15,894	15,894	[1]
Technology
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	10,710	10,710
Accumulated Amortization	(10,507)	(10,099)
Total	$ 203	$ 611
Technology | Minimum
Intangible Assets by Major Class [Line Items]
Useful Life	5 years	5 years
Technology | Maximum
Intangible Assets by Major Class [Line Items]
Useful Life	10 years	10 years
Distribution contracts
Intangible Assets by Major Class [Line Items]
Useful Life		10 years
Gross Carrying Amount		$ 8,325
Accumulated Amortization		(8,275)
Total		50
Other
Intangible Assets by Major Class [Line Items]
Gross Carrying Amount	$ 6,568	6,463
Accumulated Amortization	(6,526)	(6,408)
Total	$ 42	$ 55
Other | Minimum
Intangible Assets by Major Class [Line Items]
Useful Life	3 years	3 years
Other | Maximum
Intangible Assets by Major Class [Line Items]
Useful Life	10 years	10 years

[1] In fiscal 2018, the Company determined that no impairment was necessary on its other unamortizable intangible assets. During the 13 weeks ended July 28, 2018, the Company experienced comparable store sales that were lower than planned. The Company has evaluated whether these decreases would indicate there is a potential impairment of unamortizable intangible assets as of July 28, 2018. The Company has considered, among other factors, the Company's fiscal 2019 forecast and the current retail environment. Based on that evaluation, the Company determined that there have been no events or circumstances which would more likely than not reduce the fair value for its unamortizable intangible assets below their carrying value, during the quarter ended July 28, 2018, and an interim impairment test was not necessary as of July 28, 2018. However, the Company's trade name is at risk of impairment if B&N Retail comparable store sales continue to decline, forecasted sales expectations are not met, store closings accelerate, the assumed long-term discount rate increases, or in general the Company does not achieve its forecasted multi-year strategic plan.