Net Loss per Share - Computation of Basic and Diluted Loss per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:
Net loss attributable to Vicor Corporation	$ (4,835)	$ (4,616)	$ (10,213)	$ (9,606)
Denominator:
Denominator for basic loss per share-weighted average shares	38,542	38,538	38,541	39,852
Effect of dilutive securities:
Denominator for diluted loss per share - adjusted weighted-average shares and assumed conversions	38,542	38,538	38,541	39,852
Basic loss per share	$ (0.13)	$ (0.12)	$ (0.26)	$ (0.24)
Diluted loss per share	$ (0.13)	$ (0.12)	$ (0.26)	$ (0.24)