XML 63 R46.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Summary of Significant Accounting Policies Basis of Consolidation Policy Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Ownership Interest to be Held for Consolidation [Line Items] |  |
Unearned revenue | $ 77.0 | $ 114.3
Maximum [Member] |  |
Basis of Consolidation [Abstract] |  |
Ownership Interest To Use Equity Method | 50.00% |
Ownership Interest To Use Cost Method | 20.00% |
Minimum [Member] |  |
Basis of Consolidation [Abstract] |  |
Ownership Interest to be Held for Consolidation | 50.00% |
Noncontrolling Interests [Abstract] |  |
Ownership Interest to be Held for Consolidation | 50.00% |

X
- Definition Basis of Consolidation [Abstract] + References No definition available. + Details
Name: | itri_BasisofConsolidationAbstract
Namespace Prefix: | itri_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ownership Interest to be Held for Consolidation + References No definition available. + Details
Name: | itri_OwnershipInterestToBeHeldForConsolidation
Namespace Prefix: | itri_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ownership Interest to be Held for Consolidation [Line Items] + References No definition available. + Details
Name: | itri_OwnershipInterestToBeHeldForConsolidationLineItems
Namespace Prefix: | itri_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Entities in which the company has less than 20% investment and where they do not excercise significant influence are accounted for under the cost method. + References No definition available. + Details
Name: | itri_OwnershipInterestToUseCostMethod
Namespace Prefix: | itri_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The equity method of accounting is used for entities in which the company has a 50% or less invesment and exercises significant influence. + References No definition available. + Details
Name: | itri_OwnershipInterestToUseEquityMethod
Namespace Prefix: | itri_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.3) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.4(a).Q1) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 + Details
Name: | us-gaap_DeferredRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_NoncontrollingInterestAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |