v2.4.1.9

Restructuring Restructuring Additional Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	$ 50,857,000us-gaap_RestructuringCharges	$ 35,497,000us-gaap_RestructuringCharges	$ 1,665,000us-gaap_RestructuringCharges
Restructuring Reserve, Current	49,100,000us-gaap_RestructuringReserveCurrent	30,300,000us-gaap_RestructuringReserveCurrent
Restructuring Reserve, Noncurrent	13,800,000us-gaap_RestructuringReserveNoncurrent	6,000,000us-gaap_RestructuringReserveNoncurrent
Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	5,220,000us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember
2013 Project [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	(4,943,000)us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember	31,100,000us-gaap_RestructuringCharges / 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]
Costs incurred and charged to expense	(2,732,000)us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember
2014 Project [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	55,800,000us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember
2014 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	7,952,000us-gaap_RestructuringCharges / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember
Land, Buildings and Improvements [Member] | 2014 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	3,000,000us-gaap_RestructuringCharges / us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis = us-gaap_LandBuildingsAndImprovementsMember / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember
Machinery and Equipment [Member] | 2014 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	4,600,000us-gaap_RestructuringCharges / us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis = us-gaap_MachineryAndEquipmentMember / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember
Property, Plant and Equipment, Other Types [Member] | 2014 Project [Member] | Asset Impairment and Net (Gain) Loss on Sale or Disposal [Member]
Restructuring Cost and Reserve [Line Items]
Costs incurred and charged to expense	$ 400,000us-gaap_RestructuringCharges / us-gaap_ImpairedLongLivedAssetsHeldAndUsedByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember / us-gaap_RestructuringCostAndReserveAxis = itri_AssetImpairmentAndNetGainLossOnSaleOrDisposalMember / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember

X

- Definition

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

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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Reference 2: 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



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

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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+ References

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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