Restructuring plans - Restructuring and Related Costs (Details) - USD ($)	12 Months Ended			60 Months Ended
	Jan. 28, 2023	Jan. 29, 2022	Jan. 30, 2021	Jan. 28, 2023
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ (3,300,000)	$ 46,200,000
Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	(3,300,000)	47,600,000	$ 249,300,000
Inventory charges | Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0	1,400,000	72,800,000
Termination benefits | Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges		(1,100,000)	24,100,000	48,800,000
Store closure and other costs | Signet Path to Brillance
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ (2,200,000)	$ 22,100,000	$ 127,700,000