Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Income Statement [Abstract]
Revenues	$ 293,004	$ 319,308	$ 598,279	$ 631,960
Cost of goods sold	265,677	284,962	542,746	563,930
Gross profit	27,327	34,346	55,533	68,030
Selling, general and administrative expenses	27,262	26,948	53,510	55,236
Intangible asset amortization	2,692	2,768	5,434	5,539
Other expense (income), net	445	583	(43,067)	181
Foreign exchange loss (gain)	(90)	(11)	(1,194)	951
Earnings (loss) before the following	(2,982)	4,058	40,850	6,123
Interest expense, net	8,254	8,474	16,993	16,694
Earnings (loss) before income taxes	(11,236)	(4,416)	23,857	(10,571)
Provision for (recovery of) income taxes	(2,324)	(1,290)	7,174	(2,983)
Net earnings (loss)	(8,912)	(3,126)	16,683	(7,588)
Earnings (loss) attributable to non-controlling interests	143	48	89	(51)
Earnings (loss) attributable to SunOpta Inc.	(9,055)	(3,174)	16,594	(7,537)
Dividends and accretion on Series A Preferred Stock	(2,001)	(1,974)	(3,996)	(3,941)
Earnings (loss) attributable to common shareholders	$ (11,056)	$ (5,148)	$ 12,598	$ (11,478)
Earnings (loss) per share
Basic (in dollars per share)	$ (0.13)	$ (0.06)	$ 0.14	$ (0.13)
Diluted (in dollars per share)	$ (0.13)	$ (0.06)	$ 0.14	$ (0.13)
Weighted-average common shares outstanding (000s)
Basic	87,683	86,968	87,579	86,889
Diluted	87,683	86,968	87,743	86,889