Purchase obligations Including Hardware And Software Maintenance Contracts And Inventory Purchase Commitments (Detail) $ in Thousands	Apr. 27, 2019 USD ($)
Unrecorded Unconditional Purchase Obligation [Line Items]
Less Than 1 Year	$ 70,240
1-3 Years	44,467
3-5 Years	1,481
More Than 5 Years	0
Total	$ 116,188

Unrecorded Unconditional Purchase Obligation Due Between One To Three Years

No definition available.

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Namespace Prefix:	bks_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Unrecorded Unconditional Purchase Obligation Due Between Three to Five Years

+ References

No definition available.

+ Details

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Namespace Prefix:	bks_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration