Refers to percentage of total revenue over income from operations by each segment.

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ 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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Segment and Related Information (Details) $ in Millions	3 Months Ended					6 Months Ended		12 Months Ended
Segment and Related Information (Details) $ in Millions	Jul. 02, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 02, 2016 USD ($)	Jul. 03, 2016 USD ($)	Apr. 03, 2016 USD ($)	Jul. 02, 2017 USD ($) Segment	Jul. 03, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment						4
Net Sales	$ 414.1			$ 427.0		$ 819.1	$ 837.2
Income (Loss) from Operations	68.5			$ 39.5		130.2	97.1
% of Sales		16.80%	17.90%	18.20%	17.70%			17.70%
Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	414.1			$ 427.0		819.1	837.2
Income (Loss) from Operations	70.4			41.7		134.5	102.3
Metalcasting [Member]
Segment Reporting Information [Line Items]
Net Sales	75.7	$ 66.9	$ 63.1	68.0	$ 60.0	142.3	128.0	$ 258.0
Household, Personal Care and Specialty Products [Member]
Segment Reporting Information [Line Items]
Net Sales	39.7	39.8	42.1	44.0	45.3	80.8	89.3	171.2
Environmental Products [Member]
Segment Reporting Information [Line Items]
Net Sales	19.6	14.4	24.6	26.5	13.4	30.2	39.9	78.9
Building Materials [Member]
Segment Reporting Information [Line Items]
Net Sales	20.2	17.1	16.9	19.7	20.4	37.6	40.1	74.1
Basic Minerals [Member]
Segment Reporting Information [Line Items]
Net Sales	25.1	36.8	22.3	24.3	20.5	59.3	44.8	103.9
Specialty Minerals [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	147.0			150.6		293.2	306.2
Income (Loss) from Operations	26.9			27.6		51.3	53.3
Refractories [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	68.9			73.9		139.1	143.1
Income (Loss) from Operations	10.5			10.3		19.7	17.1
Performance Materials [Member]
Segment Reporting Information [Line Items]
Net Sales		175.0	169.0	182.5	159.6			686.1
Income (Loss) from Operations		$ 29.4	$ 30.2	33.3	$ 28.2			$ 121.1
Performance Materials [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	180.3			182.5		350.2	342.1
Income (Loss) from Operations	32.2			33.3		61.0	61.5
Energy Services [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	17.9			20.0		36.6	45.8
Income (Loss) from Operations	$ 0.8			$ (29.5)		$ 2.5	$ (29.6)