v2.4.1.9

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