v2.4.1.9

Certain Balance Sheet Components Accounts Receivable, Net, Additional Information (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Current retainage contract receivables [Member]
Long term Retainage Contract Receivables [Line Items]
Contract Receivable Retainage, Next Rolling Twelve Months	$ 4,700,000us-gaap_ContractReceivableRetainageDueInNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_CurrentRetainageContractReceivablesMember	$ 3,200,000us-gaap_ContractReceivableRetainageDueInNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_CurrentRetainageContractReceivablesMember
Unbilled Contracts Receivable	4,000,000us-gaap_UnbilledContractsReceivable / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_CurrentRetainageContractReceivablesMember	4,300,000us-gaap_UnbilledContractsReceivable / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_CurrentRetainageContractReceivablesMember
Long Term Retainage Contract Receivables [Member]
Long term Retainage Contract Receivables [Line Items]
Unbilled Receivables, Not Billable, Amount Expected to be Collected after Next Twelve Months	4,300,000us-gaap_UnbilledReceivablesNotBillableAmountExpectedToBeCollectedAfterNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_LongTermRetainageContractReceivablesMember	4,700,000us-gaap_UnbilledReceivablesNotBillableAmountExpectedToBeCollectedAfterNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_LongTermRetainageContractReceivablesMember
Contract Receivable Retainage, Due after Next Rolling Twelve Months	$ 0us-gaap_ContractReceivableRetainageDueAfterNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_LongTermRetainageContractReceivablesMember	$ 0us-gaap_ContractReceivableRetainageDueAfterNextRollingTwelveMonths / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = itri_LongTermRetainageContractReceivablesMember

X

- Details

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Namespace Prefix:	itri_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected after the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractReceivableRetainageDueAfterNextRollingTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractReceivableRetainageDueInNextRollingTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(c)(3))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c(3)

-Article 5



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 912

-SubTopic 310

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6471842&loc=d3e55302-109406

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of receivables under long-term contracts that have not been billed and were not billable that are expected to be collected after the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_UnbilledReceivablesNotBillableAmountExpectedToBeCollectedAfterNextRollingTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=itri_LongTermRetainageContractReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: