v2.4.1.9

Restructuring Restructuring Expected Costs, Costs Recognized, and Remaining Costs to be Recognized - 2013 Project (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 50,857us-gaap_RestructuringCharges	$ 35,497us-gaap_RestructuringCharges	$ 1,665us-gaap_RestructuringCharges
Employee severance costs
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	41,952us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = us-gaap_EmployeeSeveranceMember
Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	5,220us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember
Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3,685us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = us-gaap_OtherRestructuringMember
2013 Project [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	26,156us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Cost Incurred to Date		31,099us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring Charges	(4,943)us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember	31,100us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
2013 Project [Member] | Employee severance costs
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	23,691us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_EmployeeSeveranceMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Cost Incurred to Date		29,186us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_EmployeeSeveranceMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring Charges	(5,495)us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = us-gaap_EmployeeSeveranceMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_EmployeeSeveranceMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
2013 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	(1,500)us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Cost Incurred to Date		1,232us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring Charges	(2,732)us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
2013 Project [Member] | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	3,965us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_OtherRestructuringMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Cost Incurred to Date		681us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_OtherRestructuringMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring Charges	3,284us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = us-gaap_OtherRestructuringMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringCostAndReserveAxis = us-gaap_OtherRestructuringMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
2013 Project [Member] | Electricity Operating Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	15,512us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
Restructuring and Related Cost, Cost Incurred to Date		24,056us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
Restructuring Charges	(8,544)us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_ElectricityOperatingSegmentMember
2013 Project [Member] | Gas Operating Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	1,375us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
Restructuring and Related Cost, Cost Incurred to Date		4,369us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
Restructuring Charges	(2,994)us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_GasOperatingSegmentMember
2013 Project [Member] | Water Operating Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	3,130us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
Restructuring and Related Cost, Cost Incurred to Date		1,957us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
Restructuring Charges	1,173us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
Restructuring and Related Cost, Expected Cost Remaining	0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = itri_WaterOperatingSegmentMember
2013 Project [Member] | Corporate, Non-Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	6,139us-gaap_RestructuringAndRelatedCostExpectedCost1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateNonSegmentMember
Restructuring and Related Cost, Cost Incurred to Date		717us-gaap_RestructuringAndRelatedCostCostIncurredToDate1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateNonSegmentMember
Restructuring Charges	5,422us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateNonSegmentMember
Restructuring and Related Cost, Expected Cost Remaining	$ 0us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1 / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateNonSegmentMember

X

- Definition

Amount of costs incurred to date for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869



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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Amount of expected cost remaining for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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