Earnings (loss) per common share (EPS) - Schedule of Antidilutive Securities Excluded From Computation of Earnings Per Share (Details) - shares shares in Millions	3 Months Ended		6 Months Ended
	Aug. 01, 2020	Aug. 03, 2019	Aug. 01, 2020	Aug. 03, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from the calculation of earnings per share (shares)	9.4	8.6	9.1	8.6
Share awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from the calculation of earnings per share (shares)	1.7	1.4	1.4	1.4
Potential impact of preferred shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from the calculation of earnings per share (shares)	7.7	7.2	7.7	7.2