Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Commitments and contingencies - Legal proceedings (Details) - Pending litigation $ in Millions	Jan. 31, 2020 USD ($)	Jun. 02, 2016 item
Legal proceedings
Expected possible loss \| $	$ 31.0
Motor Oil MDL
Legal proceedings
Number of nationwide classes \| item		2