Accumulated other comprehensive income (loss) - Changes in Accumulated OCI by Component and Reclassifications Out of Accumulated OCI (Details) $ in Millions	6 Months Ended
Aug. 04, 2018 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 2,499.8
Other comprehensive income (loss) (“OCI”) before reclassifications	(44.7)
Amounts reclassified from AOCI to net income	(0.2)
Impact from adoption of new accounting pronouncements	(0.8)
Total other comprehensive (loss) income	(45.7)
Ending Balance	1,400.1
Foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(212.5)
Other comprehensive income (loss) (“OCI”) before reclassifications	(37.0)
Amounts reclassified from AOCI to net income	0.0
Impact from adoption of new accounting pronouncements	0.0
Total other comprehensive (loss) income	(37.0)
Ending Balance	(249.5)
Losses on available-for-sale securities, net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(0.1)
Other comprehensive income (loss) (“OCI”) before reclassifications	0.3
Amounts reclassified from AOCI to net income	0.0
Impact from adoption of new accounting pronouncements	(0.8)
Total other comprehensive (loss) income	(0.5)
Ending Balance	(0.6)
Gains (losses) on cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	0.7
Other comprehensive income (loss) (“OCI”) before reclassifications	(1.5)
Amounts reclassified from AOCI to net income	(0.5)
Impact from adoption of new accounting pronouncements	0.0
Total other comprehensive (loss) income	(2.0)
Ending Balance	(1.3)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(260.6)
Ending Balance	(306.3)
Pension Plan \| Actuarial losses
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(51.1)
Other comprehensive income (loss) (“OCI”) before reclassifications	(6.5)
Amounts reclassified from AOCI to net income	0.3
Impact from adoption of new accounting pronouncements	0.0
Total other comprehensive (loss) income	(6.2)
Ending Balance	(57.3)
Pension Plan \| Prior service credits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	2.4
Other comprehensive income (loss) (“OCI”) before reclassifications	0.0
Amounts reclassified from AOCI to net income	0.0
Impact from adoption of new accounting pronouncements	0.0
Total other comprehensive (loss) income	0.0
Ending Balance	$ 2.4

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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