v2.4.1.9

Debt Schedule of Long-Term Debt Repayments (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Debt Instrument [Line Items]
Repayments of Long-term Debt	$ 102,438,000us-gaap_RepaymentsOfLongTermDebt		$ 73,750,000us-gaap_RepaymentsOfLongTermDebt		$ 115,002,000us-gaap_RepaymentsOfLongTermDebt
2011 Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit	47,700,000us-gaap_ProceedsFromLinesOfCredit / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember		35,000,000us-gaap_ProceedsFromLinesOfCredit / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember		80,000,000us-gaap_ProceedsFromLinesOfCredit / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember
Repayments of Long-term Debt	26,250,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember		18,750,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember		15,002,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember
Secured Debt [Member]
Debt Instrument [Line Items]
Repayments of Long-term Debt	102,438,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember		73,750,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember		115,002,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember
Line of Credit [Member] | 2011 Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Repayments of Long-term Debt	$ 76,188,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_LineOfCreditMember	[1]	$ 55,000,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_LineOfCreditMember	[1]	$ 100,000,000us-gaap_RepaymentsOfLongTermDebt / us-gaap_DebtInstrumentAxis = itri_A2011SeniorSecuredCreditFacilityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_LineOfCreditMember	[1]
[1] We borrowed $47.7 million, $35.0 million and $80.0 million under the multicurrency revolving line of credit during 2014, 2013 and 2012, respectively.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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