Business Combination, Acquiree's Debt Held by Acquiror Settled Upon Acquisition

No definition available.

Name:	jnpr_BusinessCombinationAcquireesDebtHeldbyAcquirorSettledUponAcquisition
Namespace Prefix:	jnpr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Business Combination, Step Acquisition, Debt Of Acquiree Held Prior To Acquisition, Fair Value

+ References

No definition available.

+ Details

Name:	jnpr_BusinessCombinationStepAcquisitionDebtOfAcquireeHeldPriorToAcquisitionFairValue
Namespace Prefix:	jnpr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Payments for Liabilities Assumed in Business Combination

+ References

No definition available.

+ Details

Name:	jnpr_PaymentsforLiabilitiesAssumedinBusinessCombination
Namespace Prefix:	jnpr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Share-based awards assumed, fair value

+ References

No definition available.

+ Details

Name:	jnpr_Sharebasedawardsassumedfairvalue
Namespace Prefix:	jnpr_
Data Type:	xbrli:monetaryItemType
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.

+ Details

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeFairValue1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=jnpr_CyphortMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=jnpr_AppFormixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=jnpr_AurrionIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=jnpr_BTISystemsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Business Combinations, Textuals (Details) - USD ($) $ in Millions						12 Months Ended
	Sep. 18, 2017	Dec. 06, 2016	Aug. 09, 2016	Apr. 01, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 08, 2016
Business Acquisition [Line Items]
Acquisition related costs						$ 2.1	$ 11.8	$ 0.0
Cyphort
Business Acquisition [Line Items]
Payments to acquire business	$ 33.5
Share-based awards assumed, fair value	$ 3.8
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
AppFormix
Business Acquisition [Line Items]
Payments to acquire business		$ 47.9
Share-based awards assumed, fair value		$ 23.9
Business Acquisition, Percentage of Voting Interests Acquired		100.00%
Aurrion, Inc
Business Acquisition [Line Items]
Payments to acquire business			$ 74.3
Share-based awards assumed, fair value			$ 55.0
Ownership interest prior to acquisition of remaining ownership interest									18.00%
Ownership interest			100.00%
Fair value of pre-existing equity investment			$ 17.2
Fair value of pre-existing convertible debt			$ 10.4
BTI Systems, Inc
Business Acquisition [Line Items]
Payments to acquire business				$ 25.8
Share-based awards assumed, fair value				$ 8.6
Ownership interest prior to acquisition of remaining ownership interest					12.00%
Ownership interest				100.00%
Fair value of pre-existing equity investment				$ 17.1
Convertible debt held during pre-existing investment					$ 0.9
Repayment of liabilities assumed				$ 18.6