Consolidated Statements of Compehensive Loss - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss from continuing operations		$ (4,103)	$ (13,233)	$ (15,611)
Net loss from discontinued operations, net of income taxes	[1]	0	0	(9,250)
Net loss including non-controlling interest		(4,103)	(13,233)	(24,861)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment		(853)	(1,158)	(1,431)
Unrealized holding gain (loss) on available-for-sale securities		10	(5)	(15)
Total other comprehensive income (loss)		(843)	(1,163)	(1,446)
Comprehensive loss		(4,946)	(14,396)	(26,307)
Less: comprehensive loss attributable to non controlling interest		0	0	(535)
Comprehensive loss attributable to Echelon Corporation Stockholders		$ (4,946)	$ (14,396)	$ (25,772)

[1] See Note 8 for summary of amounts included representing stock-based compensation expense.