XML 69 R72.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Financial Instruments and Fair Value Measurements - Quantitative Information About Level Three Fair Value Measurements (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Apr. 24, 2015 | Apr. 25, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
ARSs Fair Value | 5,326.2 us-gaap_InvestmentsFairValueDisclosure | $ 5,003.3 us-gaap_InvestmentsFairValueDisclosure
Significant Unobservable Inputs (Level 3) |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
ARSs Fair Value |  | 0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Significant Unobservable Inputs (Level 3) | Auction Rate Securities |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
ARSs Fair Value |  | $ 36.0 us-gaap_InvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AuctionRateSecuritiesMember
Discounted Cash Flow | Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Time-to-economic maturity | 6 years 8 months 12 days |
Illiquidity premium | 1.10%us-gaap_FairValueInputsDiscountForLackOfMarketability / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Coupon rate | 1.10%ntap_FairValueInputsCouponRate / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Discounted Cash Flow | Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Time-to-economic maturity | 10 years |
Illiquidity premium | 2.80%us-gaap_FairValueInputsDiscountForLackOfMarketability / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Coupon rate | 2.70%ntap_FairValueInputsCouponRate / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Discounted Cash Flow | Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Time-to-economic maturity | 8 years 2 months 12 days |
Illiquidity premium | 1.80%us-gaap_FairValueInputsDiscountForLackOfMarketability / us-gaap_RangeAxis = us-gaap_WeightedAverageMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Coupon rate | 1.80%ntap_FairValueInputsCouponRate / us-gaap_RangeAxis = us-gaap_WeightedAverageMember / us-gaap_ValuationTechniqueAxis = us-gaap_IncomeApproachValuationTechniqueMember |
Market Comparable Securities | Minimum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Discount rate | 1.00%us-gaap_FairValueInputsDiscountRate / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_ValuationTechniqueAxis = us-gaap_MarketApproachValuationTechniqueMember |
Market Comparable Securities | Maximum |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Discount rate | 5.00%us-gaap_FairValueInputsDiscountRate / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_ValuationTechniqueAxis = us-gaap_MarketApproachValuationTechniqueMember |
Market Comparable Securities | Weighted Average |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Discount rate | 2.40%us-gaap_FairValueInputsDiscountRate / us-gaap_RangeAxis = us-gaap_WeightedAverageMember / us-gaap_ValuationTechniqueAxis = us-gaap_MarketApproachValuationTechniqueMember |

X
- Definition Fair value inputs coupon rate. + References No definition available. + Details
Name: | ntap_FairValueInputsCouponRate
Namespace Prefix: | ntap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueAssumptionsExpectedTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueInputsAssetsQuantitativeInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueInputsDiscountForLackOfMarketability
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueInputsDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 + Details
Name: | us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_IncomeApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_MarketApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |