CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands		3 Months Ended
		Mar. 29, 2019		Mar. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net income		$ 12,253	[1]	$ 12,837	[2]
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	[3]	2,339		3,671
Pension liability adjustments, net of tax	[4]	17		(116)
Total other comprehensive income		2,356		3,555
Total consolidated comprehensive income		14,609		16,392
Less: Comprehensive income attributable to noncontrolling interest				(926)
Comprehensive income attributable to Novanta Inc.		$ 14,609		$ 15,466

[1] 45,252 non-GAAP EPS performance restricted stock units granted to certain members of the executive management team and 213,219 shares of restricted stock issued to Laser Quantum former non-controlling interest holders are considered contingently issuable shares and are excluded from the calculation of the denominator as the contingent conditions had not been met as of March 29, 2019.

[2] 53,968 non-GAAP EPS performance restricted stock units granted to certain members of the executive management team were considered contingently issuable shares and were excluded from the calculation of the denominator as the contingent conditions had not been met as of March 30, 2018.

[3] The tax effect on this component of comprehensive income was nominal for all periods presented.

[4] The tax effect on this component of comprehensive income was nominal for all periods presented. See Note 3 for the total amount of pension liability adjustments reclassified out of accumulated other comprehensive income (loss).