v2.4.1.9

Goodwill Schedule of Goodwill Allocated to Reporting Segments (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Goodwill [Line Items] |  |  |
Goodwill beginning balance | $ 548,578,000 us-gaap_Goodwill | $ 701,016,000 us-gaap_Goodwill |
Goodwill, Other Changes |  | 3,958,000 us-gaap_GoodwillOtherChanges |
Goodwill impairment | (977,000)us-gaap_GoodwillImpairmentLoss | (173,249,000)us-gaap_GoodwillImpairmentLoss | 0 us-gaap_GoodwillImpairmentLoss
Effect of change in exchange rates | (46,781,000)us-gaap_GoodwillTranslationAdjustments | 16,853,000 us-gaap_GoodwillTranslationAdjustments |
Goodwill before impairment | 1,191,808,000 us-gaap_GoodwillGross | 1,318,271,000 us-gaap_GoodwillGross | 1,273,848,000 us-gaap_GoodwillGross
Accumulated impairment losses | (690,988,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss | (769,693,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss | (572,832,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
Goodwill ending balance | 500,820,000 us-gaap_Goodwill | 548,578,000 us-gaap_Goodwill | 701,016,000 us-gaap_Goodwill
Electricity Operating Segment [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill beginning balance | 60,232,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | 226,209,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |
Goodwill, Other Changes |  | 3,958,000 us-gaap_GoodwillOtherChanges / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |
Goodwill impairment | (977,000)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | (173,249,000)us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |
Effect of change in exchange rates | (3,568,000)us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | 3,314,000 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |
Goodwill before impairment | 449,668,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | 493,610,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | 475,711,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
Accumulated impairment losses | (393,981,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | (433,378,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | (249,502,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
Goodwill ending balance | 55,687,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember | 60,232,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember |
Gas Operating Segment [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill beginning balance | 394,878,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 383,743,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember |
Goodwill, Other Changes |  | 0 us-gaap_GoodwillOtherChanges / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember |
Goodwill impairment | 0 us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 0 us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember |
Effect of change in exchange rates | (35,393,000)us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 11,135,000 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember |
Goodwill before impairment | 359,485,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 394,878,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 383,743,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
Accumulated impairment losses | 0 us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 0 us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 0 us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
Goodwill ending balance | 359,485,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember | 394,878,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember |
Water Operating Segment [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill beginning balance | 93,468,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | 91,064,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember |
Goodwill, Other Changes |  | 0 us-gaap_GoodwillOtherChanges / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember |
Goodwill impairment | 0 us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | 0 us-gaap_GoodwillImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember |
Effect of change in exchange rates | (7,820,000)us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | 2,404,000 us-gaap_GoodwillTranslationAdjustments / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember |
Goodwill before impairment | 382,655,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | 429,783,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | 414,394,000 us-gaap_GoodwillGross / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
Accumulated impairment losses | (297,007,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | (336,315,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | (323,330,000)us-gaap_GoodwillImpairedAccumulatedImpairmentLoss / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
Goodwill ending balance | $ 85,648,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember | $ 93,468,000 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember |

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- Definition Amount after accumulated impairment loss of an asset representing 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 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 + Details
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