Discontinued Operations (Operating results) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 02, 2016	Apr. 04, 2015	Jan. 02, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on classification as held for sale	$ 560	$ 0
Recovery of income taxes during phase out	599	264
Earnings (loss) from discontinued operations, net of taxes	(834)	(1,081)
Loss from discontinued operations attributable to non-controlling interests	264	361
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to SunOpta Inc	(570)	(720)
Opta Minerals Inc [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues from discontinued operations	24,896	29,457
Costs of Goods Sold	(22,133)	(25,735)
Selling, general and administrative expenses	(3,024)	(2,973)
Intangible Asset Amortization	0	(505)
Other Expense, net	(794)	0
Other Income, net	0	70
Foreign exchange gain (loss)	(454)	(763)
Interest Expense	(484)	(896)
Earning (loss) before income tax	(1,993)	(1,345)
Gain on classification as held for sale	560	0
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(1,433)	(1,345)
Recovery of income taxes during phase out	599	264
Earnings (loss) from discontinued operations, net of taxes	(834)	(1,081)	$ (10,500)
Loss from discontinued operations attributable to non-controlling interests	264	361
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to SunOpta Inc	$ (570)	$ (720)	$ (7,700)