v2.4.1.9

Goodwill Goodwill Narrative (Details) (USD $) | 12 Months Ended | 1 Months Ended |
--- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | May 31, 2013 | May 01, 2012
Goodwill [Line Items] |  |  |  |  |
Goodwill impairment | $ (977,000)us-gaap_GoodwillImpairmentLoss | $ (173,249,000)us-gaap_GoodwillImpairmentLoss | $ 0 us-gaap_GoodwillImpairmentLoss |  |
Finite-Lived Intangible Assets, Gross | 748,148,000 us-gaap_FiniteLivedIntangibleAssetsGross | 804,281,000 us-gaap_FiniteLivedIntangibleAssetsGross |  |  |
Electricity Operating Segment [Member] |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Goodwill impairment | (977,000)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | (173,249,000)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |  |  |
Incremental Goodwill Impairment Expense Determined After Close of 2013 Accounting Records [Member] |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Goodwill impairment | (977,000)us-gaap_GoodwillImpairmentLoss / us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis = itri_IncrementalGoodwillImpairmentExpenseDeterminedAfterCloseof2013AccountingRecordsMember |  |  |  |
Expected Loss Recognized Resulting from Inclusion of Certain Integration Costs not Originally Reflected in Acquisition Valuation Model [Member] |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Loss on Contracts |  |  |  | 2,400,000 us-gaap_LossOnContracts / us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis = itri_ExpectedLossRecognizedResultingfromInclusionofCertainIntegrationCostsnotOriginallyReflectedinAcquisitionValuationModelMember |
Customer Relationship Associated with Error Adjustment - Balance Prior to Correction of Error [Member] |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |
Finite-Lived Intangible Assets, Gross |  |  |  |  | $ 1,500,000 us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = itri_CustomerRelationshipAssociatedwithErrorAdjustmentBalancePriortoCorrectionofErrorMember

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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Details
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- Definition Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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- Details
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- Details
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