v2.3.0.15

Certain Balance Sheet Components Accounts Receivable, Net Additional Information (Details) (USD $)	9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010
Long term Retainage Contract Receivables [Line Items]
Unbilled Contracts Receivable	$ 5,800,000	$ 2,100,000
Number of months current retainage amounts and unbilled receivables are expected to be collected	12 months
Long-term unbilled receivables and long-term retainage contract receivables	31,400,000	5,900,000
Number of months collection is not anticipated for long-term unbilled and retainage contract receivables	12 months
Number of Months Long-Term Unbilled and Retainage Contract Receivables are Expected to be Collected	18 months
Reclassified from current accounts receivables to other long-term assets [Member]
Long term Retainage Contract Receivables [Line Items]
Unbilled Contracts Receivable	7,500,000
Contract Receivable Retainage, Due after One Year	11,700,000
Long Term Retainage Contract Receivables [Member]
Long term Retainage Contract Receivables [Line Items]
Contract Receivable Retainage, Due One Year or Less	$ 887,000	$ 12,500,000

X

- Definition

Long term Retainage Receivables [Line Items]

+ Details

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

X

- Definition

Long-term unbilled receivables and Long-Term billed retainage, which has not been paid by the customer in accordance with long-term contract provisions.

+ Details

Name:	itri_LongTermUnbilledReceivablesAndLongTermBilledRetainage
Namespace Prefix:	itri
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The number of months collection is not anticipated for unbilled and retainage contract receivables as of the balance sheet date, which classifies the receivabels as long-term (greater than 12 months).

+ Details

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Namespace Prefix:	itri
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of months current retainage amounts and unbilled receivables are expected to be collected as of the balance sheet date.

+ Details

Name:	itri_NumberOfMonthsCurrentRetainageAmountsAndUnbilledReceivablesAreExpectedToBeCollected
Namespace Prefix:	itri
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of months that long-term unbilled and retainage contract receivables are expected to be collected as of the balance sheet date.

+ Details

Name:	itri_NumberOfMonthsLongTermUnbilledAndRetainageContractReceivablesAreExpectedToBeCollected
Namespace Prefix:	itri
Data Type:	us-types:durationStringItemType
Balance Type:	na
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X

- Definition

Amounts due that have been withheld by the contracting party against the reporting company's performance under the contract. These amounts will be collected upon complying with certain contractual terms or satisfaction and release by the contracting party. It is expected that such amounts will be collected more than one year from the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c(4)

-Article 5



Reference 2: 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)(4))

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



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 310

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49370-109356

+ Details

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

X

- Definition

Schedule amount of the billed retainage expected to be collected within one year from the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c

-Article 5



Reference 2: 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)(4))

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



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 310

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49370-109356

+ Details

Name:	us-gaap_ContractReceivableRetainageDueOneYearOrLess
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 912

-SubTopic 310

-Section 45

-Paragraph 2

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



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 AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 11

-Section A

-Paragraph 4, 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 4: 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

+ Details

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