Business Combinations - Additional Information (Details) € in Millions, £ in Millions									1 Months Ended	3 Months Ended		6 Months Ended	12 Months Ended
	Jul. 03, 2017 USD ($)	Jul. 03, 2017 EUR (€)	Jan. 10, 2017 USD ($)	Jan. 10, 2017 GBP (£)	May 24, 2016 USD ($)	Dec. 18, 2015 USD ($)	Nov. 09, 2015 USD ($)	Feb. 19, 2015 USD ($)	Jan. 31, 2018 USD ($)	Sep. 29, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jul. 03, 2017 EUR (€)
Business Acquisition [Line Items]
Goodwill												$ 210,988,000	$ 210,988,000	$ 108,128,000	$ 103,456,000
Gain on business acquisition													26,409,000
Acquisition and related charges													7,196,000	4,975,000	1,301,000
Amortization of intangible assets													12,096,000	8,251,000	7,611,000
Future contingent consideration												1,304,000	1,304,000	$ 2,381,000
World of Medicine GmbH
Business Acquisition [Line Items]
Percentage of shares acquired	100.00%															100.00%
Total purchase price	$ 134,934,000															€ 118.1
Intangible assets	59,732,000
Goodwill	55,632,000
Goodwill assets expected to be deductible for tax purposes	0
Revenues												49,400,000
Income (loss) from continuing operations before income taxes												(1,200,000)
Amortization of inventory fair value adjustments and purchased intangible assets, included in operating income (loss)												$ 6,000,000
Total purchase price, net of cash acquired	$ 133,534,000
World of Medicine GmbH | Maximum
Business Acquisition [Line Items]
Estimated fair value measurement period from acquisition date	1 year	1 year
World of Medicine GmbH | Revolving Credit Facility
Business Acquisition [Line Items]
Amount draw-down to finance acquisition	$ 134,800,000	€ 118.0
Laser Quantum
Business Acquisition [Line Items]
Percentage of shares acquired			35.00%
Total purchase price			$ 87,271,000
Intangible assets			38,955,000
Goodwill			31,168,000
Goodwill assets expected to be deductible for tax purposes			0
Revenues													44,700,000
Income (loss) from continuing operations before income taxes													11,300,000
Amortization of inventory fair value adjustments and purchased intangible assets, included in operating income (loss)													$ 7,100,000
Total purchase price paid by Novanta			$ 31,052,000	£ 25.5
Percentage of equity interest held before acquisition			41.00%											41.00%
Percentage of equity interest held after acquisition			76.00%
Option to purchase and sell remaining shareholders shares, year													2020
Gain on business acquisition													$ 26,400,000
Equity method investment ownership percentage on Laser Quantum			41.00%	41.00%
Non controlling interest held by remaining shareholders			24.00%
Total purchase price, net of cash acquired			$ 15,709,000
Laser Quantum | Revolving Credit Facility
Business Acquisition [Line Items]
Amount draw-down to finance acquisition			30,000,000
Thing Magic
Business Acquisition [Line Items]
Total purchase price			19,089,000
Intangible assets			7,423,000
Goodwill			9,929,000
Revenues													8,600,000
Income (loss) from continuing operations before income taxes													400,000
Amortization of inventory fair value adjustments and purchased intangible assets, included in operating income (loss)													1,500,000
Thing Magic | Revolving Credit Facility
Business Acquisition [Line Items]
Amount draw-down to finance acquisition			$ 12,000,000
World of Medicine GmbH and Laser Quantum
Business Acquisition [Line Items]
Gain on business acquisition													26,400,000
Amortization of inventory fair value adjustments													4,400,000
Acquisition and related charges													4,300,000	$ 1,200,000
Income from equity method investments													100,000	2,200,000
World of Medicine GmbH and Laser Quantum | Increase in Amortization of Intangible Assets
Business Acquisition [Line Items]
Amortization of intangible assets													5,300,000	12,500,000
World of Medicine GmbH and Laser Quantum | Increase in Interest Expense
Business Acquisition [Line Items]
Interest expense													1,400,000	3,900,000
Reach Technology Inc.
Business Acquisition [Line Items]
Percentage of shares acquired					100.00%
Total purchase price					$ 9,618,000
Intangible assets					3,953,000
Goodwill					4,715,000
Total purchase price, net of cash acquired					9,380,000
Goodwill and intangible assets expected to be deductible for tax purposes					$ 0
Skyetek Inc.
Business Acquisition [Line Items]
Total purchase price paid by Novanta						$ 2,600,000
Total purchase price, net of cash acquired						2,800,000
Future contingent consideration						200,000
Undiscounted range of outcomes, minimum						0
Undiscounted range of outcomes, maximum						$ 300,000
Contingent consideration payment										$ 100,000
Lincoln Laser Company
Business Acquisition [Line Items]
Total purchase price paid by Novanta							$ 9,800,000
Total purchase price, net of cash acquired							12,100,000
Future contingent consideration							2,300,000
Undiscounted range of outcomes, minimum							0
Undiscounted range of outcomes, maximum							$ 6,000,000
Contingent consideration payment											$ 1,400,000
Applimotion Inc.
Business Acquisition [Line Items]
Percentage of shares acquired								100.00%
Total purchase price paid by Novanta								$ 13,000,000
Total purchase price, net of cash acquired								14,000,000
Future contingent consideration								1,000,000
Undiscounted range of outcomes, minimum								0
Undiscounted range of outcomes, maximum								$ 4,000,000
Contingent consideration payment											$ 1,200,000
Applimotion Inc. | Subsequent Event
Business Acquisition [Line Items]
Contingent consideration payment									$ 2,800,000
Skyetek, Lincoln Laser and Applimotion
Business Acquisition [Line Items]
Total purchase price															29,271,000
Intangible assets															11,370,000
Goodwill															12,668,000
Total purchase price, net of cash acquired															28,940,000
Goodwill and intangible assets expected to be deductible for tax purposes															10,300,000
Future contingent consideration															3,459,000
Closed Acquisitions
Business Acquisition [Line Items]
Acquisition and related charges													$ 4,400,000	$ 200,000	$ 900,000