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					12 Months Ended
Segment and Related Information (Details) $ in Millions	Apr. 02, 2017 USD ($) Segment	Dec. 31, 2016 USD ($)	Oct. 02, 2016 USD ($)	Jul. 03, 2016 USD ($)	Apr. 03, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment	4
Net Sales	$ 405.0				$ 410.2
Income from Operations	61.7				$ 57.6
% of Sales		16.80%	17.90%	18.20%	17.70%	17.70%
Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	405.0				$ 410.2
Income from Operations	64.1				60.6
Metalcasting [Member]
Segment Reporting Information [Line Items]
Net Sales	66.6	$ 66.9	$ 63.1	$ 68.0	60.0	$ 258.0
Household, Personal Care and Specialty Products [Member]
Segment Reporting Information [Line Items]
Net Sales	41.1	39.8	42.1	44.0	45.3	171.2
Environmental Products [Member]
Segment Reporting Information [Line Items]
Net Sales	10.6	14.4	24.6	26.5	13.4	78.9
Building Materials [Member]
Segment Reporting Information [Line Items]
Net Sales	17.4	17.1	16.9	19.7	20.4	74.1
Basic Minerals [Member]
Segment Reporting Information [Line Items]
Net Sales	34.2	36.8	22.3	24.3	20.5	103.9
Specialty Minerals [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	146.2				155.6
Income from Operations	24.4				25.7
Refractories [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	70.2				69.2
Income from Operations	9.2				6.8
Performance Materials [Member]
Segment Reporting Information [Line Items]
Net Sales		175.0	169.0	182.5	159.6	686.1
Income 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	169.9				159.6
Income from Operations	28.8				28.2
Energy Services [Member] \| Reportable Segments [Member]
Segment Reporting Information [Line Items]
Net Sales	18.7				25.8
Income from Operations	$ 1.7				$ (0.1)