Common Shares and Net Income (Loss) per Common Share - Reconciliation (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Numerator:
Net income (loss) attributable to Cott Corporation - Continuing operations	$ (19.7)	$ 4.6
Net income (loss) attributable to Cott Corporation - Discontinued operations	0.0	356.8
Net (loss) income attributable to Cott Corporation	$ (19.7)	$ 361.4
Denominator:
Weighted average common shares outstanding - basic (in shares)	135,948	139,953
Basic Earnings Per Share:
Continuing operations (usd per share)	$ (0.14)	$ 0.03
Discontinued operations (usd per share)	0.00	2.55
Net income (loss) (usd per share)	$ (0.14)	$ 2.58
Denominator:
Weighted average common shares outstanding - basic (in shares)	135,948	139,953
Weighted average common shares outstanding - diluted (in shares)	135,948	142,335
Continued operations (usd per share)	$ (0.14)	$ 0.03
Discontinued operations (usd per share)	0.00	2.51
Net income (loss) (usd per share)	$ (0.14)	$ 2.54
Performance-based RSUs
Denominator:
Dilutive effect (in shares)	0	821
Time-based RSUs
Denominator:
Dilutive effect (in shares)	0	222
Stock Options
Denominator:
Dilutive effect (in shares)	0	1,339