Goodwill Goodwill Narrative (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2011 Itron International [Member]	Dec. 31, 2011 Itron International [Member]	Sep. 30, 2012 Europe [Member]	Sep. 30, 2012 North America [Member]	Dec. 31, 2011 North America [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit			$ (4,767,000)				$ 675,000	$ (5,400,000)	$ 6,700,000
The carrying value of goodwill that should have been allocated to a disposal group									1,300,000
Goodwill impairment	$ 0	$ 540,400,000	$ 0	$ 540,400,000	$ 540,400,000	$ 584,800,000