Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net loss (Numerator):
Net loss from continuing operations attributable to Echelon Corporation Stockholders	$ (1,047)	$ (7,226)	$ (7,634)	$ (13,058)
Net loss from discontinued operations attributable to Echelon Corporation Stockholders	0	(1,962)	0	(8,715)
Net loss attributable to Echelon Corporation Stockholders	$ (1,047)	$ (9,188)	$ (7,634)	$ (21,773)
Shares (Denominator):
Weighted average common shares outstanding (shares)	44,128	43,507	44,068	43,367
Shares used in basic computation (shares)	44,128	43,507	44,068	43,367
Common shares issuable upon exercise of stock options (treasury stock method)	0	0	0	0
Shares used in diluted computation (shares)	44,128	43,507	44,068	43,367
Net loss per share:
Basic and diluted net loss per share from continuing operations attributable to Echelon Corporation Stockholders (usd per shares)	$ (0.02)	$ (0.17)	$ (0.17)	$ (0.30)
Basic and diluted net loss per share from discontinued operations attributable to Echelon Corporation Stockholders (usd per shares)	0.00	(0.05)	0.00	(0.20)
Basic and diluted net loss attributable to Echelon Corporation Stockholders (usd per shares)	$ (0.02)	$ (0.21)	$ (0.17)	$ (0.50)