v2.4.1.9

Quarterly Results (Unaudited) Quarterly Results Narrative (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Results [Line Items]
Goodwill, Impairment Loss	$ 977,000us-gaap_GoodwillImpairmentLoss	$ 173,249,000us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss
Restructuring Charges	50,857,000us-gaap_RestructuringCharges	35,497,000us-gaap_RestructuringCharges	1,665,000us-gaap_RestructuringCharges
2014 Project [Member]
Quarterly Results [Line Items]
Restructuring Charges	55,800,000us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2014ProjectMember
2013 Project [Member]
Quarterly Results [Line Items]
Restructuring Charges	$ (4,943,000)us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember	$ 31,100,000us-gaap_RestructuringCharges / us-gaap_RestructuringPlanAxis = itri_A2013ProjectMember

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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

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-SubTopic 10

-Section 45

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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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-Number Topic 5

-Section P

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