Document and Entity Information Document	9 Months Ended
	Sep. 30, 2017 shares
Entity Information [Line Items]
Entity Registrant Name	ITRON INC /WA/
Entity Central Index Key	0000780571
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Trading Symbol	ITRI
Entity Common Stock, Shares Outstanding	38,725,212