Amount potentially available for additional borrowing on the Line of Credit Facility.

No definition available.

Name:	ntap_LineOfCreditFacilityAdditionalExpansionOptionAvailable
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Balance Type:	credit
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- Definition

Number of extensions potentially available to the borrower under the line of credit facility.

+ References

No definition available.

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- Definition

Term of extension period for line of credit facility.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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Data Type:	xbrli:dateItemType
Balance Type:	na
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Period Type:	instant

- Definition

The value of notes retired (or transferred to another entity) in noncash investing or financing transactions.

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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Balance Type:	debit
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- Definition

The liability due as of the balance sheet date for leasebacks accounted for using the deposit method.

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- Definition

The portion of the deferred gain that was recognized in the current period.

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

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- Definition

Value transferred out of real estate owned (REO) in noncash transactions.

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Financing Arrangements - Additional Information (Detail)		1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 12, 2016 USD ($) Extension	Feb. 29, 2016 USD ($)	Jan. 27, 2017 USD ($)	Apr. 28, 2017 USD ($)	Apr. 29, 2016 USD ($)	Apr. 24, 2015 USD ($)
Debt Instrument [Line Items]
Short-term loan		$ 870,000,000		$ 0	$ 870,000,000	$ 0
Short-term loan maturity date				Nov. 02, 2016
Non-cash sale of properties, net book value			$ 9,000,000	$ 9,000,000
Non-cash extinguishment of financing obligations			19,000,000	19,000,000	0	0
Gain on sale of properties			$ 10,000,000	10,000,000	51,000,000	$ 0
Sale leaseback transaction, remaining financing obligations				130,000,000	19,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, amount	$ 600,000,000
Credit facility, date expiry	Dec. 10, 2021
Credit facility, increase in facility	$ 300,000,000
Credit facility, number of extensions \| Extension	2
Credit facility, extensions period	1 year
Credit facility, outstanding borrowings				0
Revolving Credit Facility \| Letter Of Credit Sub Facility
Debt Instrument [Line Items]
Credit facility, amount	$ 50,000,000
Credit facility, outstanding letters of credit				0
Commercial Paper
Debt Instrument [Line Items]
Notes issued, principal amount				$ 500,000,000
Weighted-average interest rate				1.26%
Commercial Paper \| Maximum
Debt Instrument [Line Items]
Notes issued, principal amount	$ 600,000,000
Debt instrument maturity period	397 days			38 days
Commercial Paper \| Minimum
Debt Instrument [Line Items]
Debt instrument maturity period				7 days
Senior Notes
Debt Instrument [Line Items]
Notes issued, principal amount				$ 1,500,000,000	1,500,000,000
Senior Notes \| Due June 2021
Debt Instrument [Line Items]
Notes issued, interest rate				3.375%
Notes issued, principal amount				$ 500,000,000	500,000,000
Senior Notes \| Due December 2017
Debt Instrument [Line Items]
Notes issued, interest rate				2.00%
Notes issued, principal amount				$ 750,000,000	750,000,000
Senior Notes \| Due December 2022
Debt Instrument [Line Items]
Notes issued, interest rate				3.25%
Notes issued, principal amount				$ 250,000,000	$ 250,000,000