Summary of Fair Values of Assets Acquired and Liabilities Assumed Purchase Price Allocation (Details) $ in Thousands, € in Millions, £ in Millions				12 Months Ended
	Jul. 31, 2019 USD ($)	Jul. 31, 2019 EUR (€)	May 01, 2018 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 EUR (€)	Jul. 31, 2019 EUR (€)	May 01, 2018 GBP (£)
Business Acquisition [Line Items]
Goodwill				$ 285,980	$ 274,710
Total purchase price paid by Novanta						$ 33,500
Less: issuance of common shares					10,900
Less: deferred cash consideration					$ 27,735
ARGES GmbH
Business Acquisition [Line Items]
Cash	$ 3,159
Accounts receivable	1,430
Inventories	7,129
Property, plant and equipment	14,095
Intangible assets	24,713
Goodwill	42,951
Other assets	2,244
Total assets acquired	95,721
Accounts payable	2,598
Deferred tax liabilities	5,510
Other liabilities	14,462
Total liabilities assumed	22,570
Total assets acquired, net of liabilities assumed	73,151							€ 65.7
Total purchase price paid by Novanta	26,700	€ 24.0
Less: cash acquired	3,159
Total purchase price, net of cash acquired	69,992
Less: contingent consideration	7,870			5,100			€ 4.1	7.1
Less: issuance of common shares	10,900	€ 9.8
Less: deferred cash consideration	27,664						€ 25.0	€ 24.8
Net cash used for acquisition of businesses	$ 23,558
Med X Change, Inc and Ingenia-CAT, S.L.
Business Acquisition [Line Items]
Cash				1,000
Accounts receivable				1,739
Inventories				2,372
Property, plant and equipment				496
Intangible assets				22,376
Goodwill				13,388
Other assets				601
Total assets acquired				41,972
Accounts payable				604
Deferred tax liabilities				2,399
Other liabilities				910
Total liabilities assumed				3,913
Total assets acquired, net of liabilities assumed				38,059
Less: cash acquired				1,000
Total purchase price, net of cash acquired				37,059
Less: contingent consideration				6,569
Net cash used for acquisition of businesses				29,585
Less: purchase price holdback				$ 905
Zettlex Holdings Limited
Business Acquisition [Line Items]
Cash			$ 3,776
Accounts receivable			2,237
Inventories			928
Property, plant and equipment			2,590
Intangible assets			14,585
Goodwill			11,790
Other assets			145
Total assets acquired			36,051
Accounts payable			509
Deferred tax liabilities			2,481
Accrued expenses and other liabilities			1,035
Total liabilities assumed			4,025
Total assets acquired, net of liabilities assumed			32,026						£ 23.3
Less: cash acquired			3,776
Total purchase price, net of cash acquired			$ 28,250