SMTC Corporation Quarterly report pursuant to Section 13 or 15(d)

Note 9 - Segmented Information (Details Textual) - Customer Concentration Risk [Member]	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017
Sales Revenue, Net [Member]
Number of Major Customers	3	2	2	2
Sales Revenue, Net [Member] \| Major Customer1 [Member]
Concentration Risk, Percentage	12.80%	14.00%	13.50%	12.30%
Sales Revenue, Net [Member] \| Major Customer2 [Member]
Concentration Risk, Percentage	12.00%	12.80%	10.40%	11.50%
Sales Revenue, Net [Member] \| Major Customer3 [Member]
Concentration Risk, Percentage	10.90%
Accounts Receivable [Member]
Number of Major Customers			3		3
Accounts Receivable [Member] \| Major Customer1 [Member]
Concentration Risk, Percentage			14.70%		14.00%
Accounts Receivable [Member] \| Major Customer2 [Member]
Concentration Risk, Percentage			10.30%		14.00%
Accounts Receivable [Member] \| Major Customer3 [Member]
Concentration Risk, Percentage			10.30%		12.00%