Condensed consolidating financial information - Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Feb. 02, 2019	Feb. 03, 2018	Jan. 28, 2017	Jan. 30, 2016
Current assets:
Cash and cash equivalents	$ 195.4	$ 225.1	$ 98.7	$ 137.7
Accounts receivable, held for sale	4.2	0.0
Accounts receivable, net	19.5	692.5
Intra-entity receivables, net	0.0	0.0
Other receivables	72.5	87.2
Other current assets	171.5	158.2
Income taxes	5.8	2.6
Inventories	2,386.9	2,280.5
Total current assets	2,855.8	3,446.1
Non-current assets:
Property, plant and equipment, net	800.5	877.9
Goodwill	296.6	821.7	517.6
Intangible assets, net	265.0	481.5
Investment in subsidiaries	0.0
Intra-entity receivables, net	0.0
Other assets	150.6	171.2
Deferred tax assets	21.0	1.4
Retirement benefit asset	30.6	39.8
Total assets	4,420.1	5,839.6
Current liabilities:
Loans and overdrafts	78.8	44.0
Accounts payable	153.7	237.0
Intra-entity payables, net		0.0
Accrued expenses and other current liabilities	502.8	448.0
Deferred revenue	270.0	288.6
Income taxes	27.7	19.6
Total current liabilities	1,033.0	1,037.2
Non-current liabilities:
Long-term debt	649.6	688.2
Other liabilities	224.1	239.6
Deferred revenue	696.5	668.9
Deferred tax liabilities	0.0	92.3
Total liabilities	2,603.2	2,726.2
Series A redeemable convertible preferred shares		613.6
Shareholders’ equity:
Total shareholders’ equity	1,201.6	2,499.8	2,490.2	3,060.7
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	4,420.1	5,839.6
Consolidation, Eliminations
Current assets:
Cash and cash equivalents	0.0	0.0	0.0	0.0
Accounts receivable, held for sale	0.0
Accounts receivable, net	0.0	0.0
Intra-entity receivables, net	(311.3)	(169.8)
Other receivables	0.0	0.0
Other current assets	0.0	0.0
Income taxes	0.0	0.0
Inventories	0.0	0.0
Total current assets	(311.3)	(169.8)
Non-current assets:
Property, plant and equipment, net	0.0
Goodwill	0.0
Intangible assets, net	0.0	0.0
Investment in subsidiaries	(1,834.5)	(4,919.8)
Intra-entity receivables, net	(2,988.0)	(3,259.0)
Other assets	0.0
Deferred tax assets	0.0
Retirement benefit asset	0.0
Total assets	(5,133.8)	(8,348.6)
Current liabilities:
Loans and overdrafts	0.0	0.0
Accounts payable	0.0	0.0
Intra-entity payables, net	(311.3)	(169.8)
Accrued expenses and other current liabilities	0.0	0.0
Deferred revenue	0.0	0.0
Income taxes	0.0	0.0
Total current liabilities	(311.3)	(169.8)
Non-current liabilities:
Intra-entity payables, net	(2,988.0)	(3,259.0)
Total liabilities	(3,299.3)	(3,428.8)
Series A redeemable convertible preferred shares		0.0
Shareholders’ equity:
Total shareholders’ equity	(1,834.5)	(4,919.8)
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	(5,133.8)	(8,348.6)
Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and cash equivalents	146.7	150.5	70.3	102.0
Accounts receivable, held for sale	4.2
Accounts receivable, net	10.1	692.5
Intra-entity receivables, net	83.4	0.0
Other receivables	46.5	62.0
Other current assets	169.4	154.4
Income taxes	5.1	2.6
Inventories	2,302.6	2,201.3
Total current assets	2,768.0	3,263.3
Non-current assets:
Property, plant and equipment, net	789.6	870.1
Goodwill	206.3	516.4
Intangible assets, net	244.0	410.9
Investment in subsidiaries	(15.7)	1,163.6
Intra-entity receivables, net	0.0
Other assets	133.4	140.1
Deferred tax assets	24.5	1.3
Retirement benefit asset	30.6	39.8
Total assets	4,180.7	6,405.5
Current liabilities:
Loans and overdrafts	79.5	44.7
Accounts payable	119.7	202.2
Intra-entity payables, net		158.5
Accrued expenses and other current liabilities	450.4	397.5
Deferred revenue	257.6	276.2
Income taxes	26.4	36.7
Total current liabilities	933.6	1,115.8
Non-current liabilities:
Long-term debt	253.6	293.0
Intra-entity payables, net	2,988.0	3,259.0
Other liabilities	219.4	233.0
Deferred revenue	696.5	668.9
Deferred tax liabilities		76.7
Total liabilities	5,091.1	5,646.4
Shareholders’ equity:
Total shareholders’ equity	(910.4)	759.1
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	4,180.7	6,405.5
Non-Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and cash equivalents	48.4	72.8	26.6	33.7
Accounts receivable, held for sale	0.0
Accounts receivable, net	9.4
Intra-entity receivables, net	220.0	166.9
Other receivables	26.0	25.2
Other current assets	2.1	3.8
Income taxes	0.7
Inventories	84.3	79.2
Total current assets	390.9	347.9
Non-current assets:
Property, plant and equipment, net	10.9	7.8
Goodwill	90.3	305.3
Intangible assets, net	21.0	70.6
Investment in subsidiaries	(305.5)	606.0
Intra-entity receivables, net	2,588.0	2,859.0
Other assets	17.2	31.1
Deferred tax assets	(3.5)	0.1
Retirement benefit asset	0.0
Total assets	2,809.3	4,227.8
Current liabilities:
Loans and overdrafts	0.0	0.0
Accounts payable	34.0	34.8
Intra-entity payables, net	0.0	0.0
Accrued expenses and other current liabilities	22.3	20.9
Deferred revenue	12.4	12.4
Income taxes	0.5	(16.9)
Total current liabilities	69.2	51.2
Non-current liabilities:
Other liabilities	4.7	6.6
Deferred tax liabilities		15.6
Total liabilities	73.9	73.4
Shareholders’ equity:
Total shareholders’ equity	2,735.4	4,154.4
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	2,809.3	4,227.8
Signet Jewelers Limited | Reportable Legal Entities
Current assets:
Cash and cash equivalents	0.2	1.7	1.7	1.9
Accounts receivable, held for sale	0.0
Accounts receivable, net	0.0	0.0
Other receivables	0.0	0.0
Other current assets		0.0
Income taxes	0.0	0.0
Inventories	0.0	0.0
Total current assets	0.2	1.7
Non-current assets:
Property, plant and equipment, net	0.0
Goodwill	0.0
Intangible assets, net	0.0	0.0
Investment in subsidiaries	2,155.7	3,150.2
Intra-entity receivables, net	0.0
Other assets	0.0
Deferred tax assets	0.0
Retirement benefit asset	0.0
Total assets	2,155.9	3,151.9
Current liabilities:
Loans and overdrafts	0.0	0.0
Accounts payable	0.0	0.0
Intra-entity payables, net	311.3	11.3
Accrued expenses and other current liabilities	27.7	27.2
Deferred revenue	0.0	0.0
Income taxes	0.0	0.0
Total current liabilities	339.0	38.5
Non-current liabilities:
Total liabilities	339.0	38.5
Shareholders’ equity:
Total shareholders’ equity	1,201.6	2,499.8
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	2,155.9	3,151.9
Signet UK Finance plc | Reportable Legal Entities
Current assets:
Cash and cash equivalents	0.1	0.1	$ 0.1	$ 0.1
Accounts receivable, held for sale	0.0
Accounts receivable, net	0.0	0.0
Intra-entity receivables, net	7.9	2.9
Other receivables	0.0	0.0
Other current assets		0.0
Income taxes	0.0	0.0
Inventories	0.0	0.0
Total current assets	8.0	3.0
Non-current assets:
Property, plant and equipment, net	0.0	0.0
Goodwill	0.0	0.0
Intangible assets, net	0.0	0.0
Investment in subsidiaries	0.0	0.0
Intra-entity receivables, net	400.0	400.0
Other assets		0.0
Deferred tax assets	0.0	0.0
Retirement benefit asset	0.0	0.0
Total assets	408.0	403.0
Current liabilities:
Loans and overdrafts	(0.7)	(0.7)
Accounts payable	0.0	0.0
Intra-entity payables, net	0.0	0.0
Accrued expenses and other current liabilities	2.4	2.4
Deferred revenue	0.0	0.0
Income taxes	0.8	(0.2)
Total current liabilities	2.5	1.5
Non-current liabilities:
Long-term debt	396.0	395.2
Intra-entity payables, net		0.0
Other liabilities		0.0
Deferred revenue		0.0
Total liabilities	398.5	396.7
Shareholders’ equity:
Total shareholders’ equity	9.5	6.3
Total liabilities, redeemable convertible preferred shares and shareholders’ equity	408.0	403.0
Series A Redeemable Convertible Preferred Stock
Non-current liabilities:
Series A redeemable convertible preferred shares	615.3	613.6
Series A Redeemable Convertible Preferred Stock | Consolidation, Eliminations
Non-current liabilities:
Series A redeemable convertible preferred shares	0.0
Series A Redeemable Convertible Preferred Stock | Guarantor Subsidiaries | Reportable Legal Entities
Non-current liabilities:
Series A redeemable convertible preferred shares	0.0	0.0
Series A Redeemable Convertible Preferred Stock | Non-Guarantor Subsidiaries | Reportable Legal Entities
Non-current liabilities:
Series A redeemable convertible preferred shares	0.0	0.0
Series A Redeemable Convertible Preferred Stock | Signet Jewelers Limited | Reportable Legal Entities
Non-current liabilities:
Series A redeemable convertible preferred shares	615.3	613.6
Series A Redeemable Convertible Preferred Stock | Signet UK Finance plc | Reportable Legal Entities
Non-current liabilities:
Series A redeemable convertible preferred shares	$ 0.0	$ 0.0