Note 15.3 - Commitments and Contingencies, Legal Proceedings Level 4 (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011 day Year issuers month
Loss Contingencies [Line Items]
Number of other issuers included in IPO lawsuit allegations	300
Estimated Incremental Tax Liability Excluding Interest And Penalties Related to PNOD	$ 92
Estimated incremental tax liability excluding interest and penalties related to NOPA	$ 807

Name:

jnpr_EstimatedIncrementalTaxLiabilityExcludingInterestAndPenaltiesRelatedToNopa

Namespace Prefix:

jnpr

Data Type:

xbrli:monetaryItemType

Balance Type:

credit

Period Type:

instant