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Pertains to the number of countries where the entity have operations.

No definition available.

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Namespace Prefix:	nati_
Data Type:	xbrli:integerItemType
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Percentage entered into by the entity to hedge risk of loss related to forecasted exposures in selected currencies (primarily in Euro, Japanese yen, British pound sterling and Hungarian forint) and outstanding foreign denominated net receivables or net payables.

No definition available.

Name:	nati_PercentageOfDerivativeRiskHedged
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Data Type:	num:percentItemType
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Period Type:	instant

Percentage of sales (as compared to total revenues) outside of the Americas during the period.

No definition available.

Name:	nati_PercentageOfSalesOutsideOfAmericasDuringPeriod
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Data Type:	num:percentItemType
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Number of years of protection against the reduction in value caused by a fluctuation in foreign currency exchange rates of forecasted foreign currency cash flows resulting from international sales, maximum.

No definition available.

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No definition available.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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Data Type:	xbrli:monetaryItemType
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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.

No definition available.

Name:	us-gaap_DerivativeLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DerivativeTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForwardContractsMember
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Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_OperatingExpenseMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DerivativeInstrumentRiskAxis=nati_OtherDerivativesMember
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