Revenue recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 02, 2025	Aug. 03, 2024	Aug. 02, 2025	Aug. 03, 2024
Disaggregation of Revenue [Line Items]
Total sales	$ 1,535.1	$ 1,491.0	$ 3,076.7	$ 3,001.8
Bridal
Disaggregation of Revenue [Line Items]
Total sales	674.2	671.1	1,366.9	1,352.4
Fashion
Disaggregation of Revenue [Line Items]
Total sales	542.9	534.9	1,092.3	1,080.2
Watches
Disaggregation of Revenue [Line Items]
Total sales	80.7	71.7	150.2	135.2
Service sales
Disaggregation of Revenue [Line Items]
Total sales	192.3	179.7	383.6	364.2
Other
Disaggregation of Revenue [Line Items]
Total sales	45.0	33.6	83.7	69.8
Kay
Disaggregation of Revenue [Line Items]
Total sales	569.5	542.6	1,148.6	1,110.1
Zales
Disaggregation of Revenue [Line Items]
Total sales	270.0	255.5	553.2	512.2
Jared
Disaggregation of Revenue [Line Items]
Total sales	262.2	251.6	522.2	501.1
Blue Nile
Disaggregation of Revenue [Line Items]
Total sales	74.7	78.5	152.3	154.3
James Allen
Disaggregation of Revenue [Line Items]
Total sales	36.9	52.8	76.3	110.7
Diamonds Direct
Disaggregation of Revenue [Line Items]
Total sales	87.1	89.3	171.2	171.9
Banter by Piercing Pagoda
Disaggregation of Revenue [Line Items]
Total sales	75.6	77.6	157.8	161.2
Peoples
Disaggregation of Revenue [Line Items]
Total sales	47.8	43.6	88.6	82.8
International segment
Disaggregation of Revenue [Line Items]
Total sales	91.8	86.5	171.9	163.7
Other
Disaggregation of Revenue [Line Items]
Total sales	19.5	13.0	34.6	33.8
Store
Disaggregation of Revenue [Line Items]
Total sales	1,198.3	1,147.8	2,386.4	2,302.9
E-commerce
Disaggregation of Revenue [Line Items]
Total sales	317.6	332.3	656.3	670.2
Other
Disaggregation of Revenue [Line Items]
Total sales	19.2	10.9	34.0	28.7
North America
Disaggregation of Revenue [Line Items]
Total sales	1,426.7	1,397.6	2,877.2	2,817.6
North America \| Bridal
Disaggregation of Revenue [Line Items]
Total sales	633.0	631.2	1,289.6	1,277.2
North America \| Fashion
Disaggregation of Revenue [Line Items]
Total sales	523.9	517.2	1,056.9	1,047.3
North America \| Watches
Disaggregation of Revenue [Line Items]
Total sales	55.5	48.7	103.3	91.4
North America \| Service sales
Disaggregation of Revenue [Line Items]
Total sales	185.9	173.8	371.3	352.4
North America \| Other
Disaggregation of Revenue [Line Items]
Total sales	28.4	26.7	56.1	49.3
North America \| Kay
Disaggregation of Revenue [Line Items]
Total sales	569.5	542.6	1,148.6	1,110.1
North America \| Zales
Disaggregation of Revenue [Line Items]
Total sales	270.0	255.5	553.2	512.2
North America \| Jared
Disaggregation of Revenue [Line Items]
Total sales	262.2	251.6	522.2	501.1
North America \| Blue Nile
Disaggregation of Revenue [Line Items]
Total sales	74.7	78.5	152.3	154.3
North America \| James Allen
Disaggregation of Revenue [Line Items]
Total sales	36.9	52.8	76.3	110.7
North America \| Diamonds Direct
Disaggregation of Revenue [Line Items]
Total sales	87.1	89.3	171.2	171.9
North America \| Banter by Piercing Pagoda
Disaggregation of Revenue [Line Items]
Total sales	75.6	77.6	157.8	161.2
North America \| Peoples
Disaggregation of Revenue [Line Items]
Total sales	47.8	43.6	88.6	82.8
North America \| International segment
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
North America \| Other
Disaggregation of Revenue [Line Items]
Total sales	2.9	6.1	7.0	13.3
North America \| Store
Disaggregation of Revenue [Line Items]
Total sales	1,125.6	1,080.2	2,250.9	2,174.5
North America \| E-commerce
Disaggregation of Revenue [Line Items]
Total sales	298.5	313.4	619.9	634.9
North America \| Other
Disaggregation of Revenue [Line Items]
Total sales	2.6	4.0	6.4	8.2
International segment
Disaggregation of Revenue [Line Items]
Total sales	91.8	86.5	171.9	163.7
International segment \| Bridal
Disaggregation of Revenue [Line Items]
Total sales	41.2	39.9	77.3	75.2
International segment \| Fashion
Disaggregation of Revenue [Line Items]
Total sales	19.0	17.7	35.4	32.9
International segment \| Watches
Disaggregation of Revenue [Line Items]
Total sales	25.2	23.0	46.9	43.8
International segment \| Service sales
Disaggregation of Revenue [Line Items]
Total sales	6.4	5.9	12.3	11.8
International segment \| Other
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Kay
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Zales
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Jared
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Blue Nile
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| James Allen
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Diamonds Direct
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Banter by Piercing Pagoda
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Peoples
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| International segment
Disaggregation of Revenue [Line Items]
Total sales	91.8	86.5	171.9	163.7
International segment \| Other
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
International segment \| Store
Disaggregation of Revenue [Line Items]
Total sales	72.7	67.6	135.5	128.4
International segment \| E-commerce
Disaggregation of Revenue [Line Items]
Total sales	19.1	18.9	36.4	35.3
International segment \| Other
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other
Disaggregation of Revenue [Line Items]
Total sales	16.6	6.9	27.6	20.5
Other \| Bridal
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Fashion
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Watches
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Service sales
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Other
Disaggregation of Revenue [Line Items]
Total sales	16.6	6.9	27.6	20.5
Other \| Kay
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Zales
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Jared
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Blue Nile
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| James Allen
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Diamonds Direct
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Banter by Piercing Pagoda
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Peoples
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| International segment
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Other
Disaggregation of Revenue [Line Items]
Total sales	16.6	6.9	27.6	20.5
Other \| Store
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| E-commerce
Disaggregation of Revenue [Line Items]
Total sales	0.0	0.0	0.0	0.0
Other \| Other
Disaggregation of Revenue [Line Items]
Total sales	$ 16.6	$ 6.9	$ 27.6	$ 20.5