v2.4.1.9

Defined Benefit Pension Plans Defined Benefit Pension Plan Employer Contributions Additional Information (Details) (USD $) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items] |  |
Estimated Future Employer Contributions in Next Fiscal Year | $ 426,000 us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear |
Fair Value of Plan Assets [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Contributions by Employer | $ 375,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = itri_FairValueOfPlanAssetsMember | $ 436,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = itri_FairValueOfPlanAssetsMember
Defined Benefit Obligations [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Change in Discount Rate | 140 basis point |

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- Definition Defined Benefit Plan, Change in Discount Rate assumption used to determine the benefit obligation + References No definition available. + Details
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- Definition The increase in the fair value of plan assets from contributions made by the employer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Details
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