CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Income Statement [Abstract]
Revenue	$ 150,400	$ 119,102	$ 297,365	$ 228,076
Cost of revenue	85,171	65,613	169,977	128,493
Gross profit	65,229	53,489	127,388	99,583
Operating expenses:
Research and development and engineering	12,551	9,004	24,540	18,219
Selling, general and administrative	29,231	23,810	58,451	46,684
Amortization of purchased intangible assets	3,893	3,347	7,591	6,196
Restructuring, acquisition and divestiture related costs	2,439	1,581	2,464	2,398
Total operating expenses	48,114	37,742	93,046	73,497
Operating income	17,115	15,747	34,342	26,086
Interest income (expense), net	(2,561)	(1,435)	(4,919)	(2,763)
Foreign exchange transaction gains (losses), net	177	486	(230)	485
Other income (expense), net	(46)	(119)	(87)	(150)
Gain on acquisition of business				26,409
Income before income taxes	14,685	14,679	29,106	50,067
Income tax provision	3,060	4,689	4,644	5,803
Consolidated net income	11,625	9,990	24,462	44,264
Less: Net income attributable to noncontrolling interest	(625)	(588)	(1,551)	(610)
Net income attributable to Novanta Inc.	$ 11,000	$ 9,402	$ 22,911	$ 43,654
Earnings per common share attributable to Novanta Inc. (Note 5):
Basic	$ 0.32	$ 0.16	$ 0.51	$ 1.15
Diluted	$ 0.32	$ 0.16	$ 0.50	$ 1.13
Weighted average common shares outstanding—basic	34,949	34,827	34,919	34,796
Weighted average common shares outstanding—diluted	35,474	35,463	35,451	35,294