Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Name:	us-gaap_DeferredRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Revenue Recognition - Additional Information (Detail) - USD ($)	6 Months Ended
	Oct. 29, 2016	Apr. 30, 2016	Oct. 31, 2015
Deferred Revenue Arrangement [Line Items]
Estimated life of NOOK, years	2 years
Nook
Deferred Revenue Arrangement [Line Items]
Recognized over	2 years
Deferred revenue	$ 354,000	$ 160,000	$ 675,000
Nook \| Minimum
Deferred Revenue Arrangement [Line Items]
Average percent, NOOK's sales price	0.00%
Nook \| Maximum
Deferred Revenue Arrangement [Line Items]
Average percent, NOOK's sales price	5.00%
Annual Fee
Deferred Revenue Arrangement [Line Items]
Non-refundable, after first 30 days, annual fee	$ 25.00