Accrual for estimated carrying charges or obsolete materials charges.

No definition available.

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- Definition

Energy Services Agreement Duration

+ References

No definition available.

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- Definition

Unrecorded Unconditional Purchase Obligation, Variable Component Estimate

+ References

No definition available.

+ Details

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

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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Balance Type:	credit
Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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-Subparagraph (b)(3)
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Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 4
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

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-Paragraph 5
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of tax liability from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of unrecognized tax benefits.

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-Name Accounting Standards Codification
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-SubTopic 10
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- 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).

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-SubTopic 10
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-Paragraph 4
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Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_IndemnificationGuaranteeMember
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Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=jnpr_EnergyServicesAgreementMember
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandAndBuildingMember
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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Guarantor Obligations [Line Items]
Minimum fixed fees payable	$ 113.8
Operating lease rent expense	42.0	$ 0.0	$ 0.0
Rent expense		39.0	39.3
Accrued estimated carrying charges	28.6
Long-term debt	1,683.9
Income taxes payable		245.2
Unrecognized tax benefits	151.3	178.1	$ 264.5	$ 223.1
Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	9.0	11.9
Financing guarantees, bank guarantees, and standby letters of credit
Guarantor Obligations [Line Items]
Guarantor obligations, current carrying value	30.6	$ 23.1
Master Service Agreement
Guarantor Obligations [Line Items]
Expected payment	300.0
Energy Services Agreement
Guarantor Obligations [Line Items]
Expected payment	$ 29.0
Energy services agreement duration	15 years
Facilities \| Minimum
Guarantor Obligations [Line Items]
Lease term	1 year
Facilities \| Maximum
Guarantor Obligations [Line Items]
Lease term	10 years
Equipment \| Minimum
Guarantor Obligations [Line Items]
Lease term	1 year
Equipment \| Maximum
Guarantor Obligations [Line Items]
Lease term	4 years
Other Lease Arrangement \| Maximum
Guarantor Obligations [Line Items]
Lease term	10 years
Long-term Income Taxes
Guarantor Obligations [Line Items]
Unrecognized tax benefits	$ 127.4