Commitments and contingencies - Legal proceedings (Detail)	Feb. 03, 2017 USD ($) item
Motor Oil MDL \| Pending litigation
Legal proceedings
Number of nationwide classes	2
Number of statewide sub-classes	16
Number of suits filed	22
California County Environmental Authorities \| Minimum
Legal proceedings
Expected possible loss \| $	$ 100,000

The number of nationwide classes for which certification is sought.

No definition available.

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- Definition

The number of statewide sub-classes for which certification is sought.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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- Details

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- Details

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