Revenue Recognition Revenue Contract Assets and Liabilities Rollforward (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Revenue Recognition and Deferred Revenue [Abstract]
Beginning balance, January 1	$ 102,130
Revenues recognized from beginning contract liability	(36,215)
Increases due to amounts collected or due	90,592
Revenues recognized from current period increases	(40,740)
Other	(8,889)
Ending balance, March 31	$ 106,878

Contract with Customer, Liability, Revenue Recognized From Current Period

No definition available.

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Namespace Prefix:	itri_
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Balance Type:	credit
Period Type:	duration

- Definition

Contract with Customer, Other adjustments

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Contract with Customer, net

+ References

No definition available.

+ Details

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Namespace Prefix:	itri_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

+ Details

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- References

No definition available.

+ Details

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