Business Combinations - Schedule of Purchase Price Allocation (Detail) - Beck Trading - USD ($) $ in Millions	Nov. 01, 2016	Dec. 31, 2017
Business Acquisition
Consideration paid at closing	$ 23.6
Purchase price allocation:
Inventories	10.6	$ 10.6
Property, plant and equipment	6.8
Equity method investment	6.1
Prepaid expenses, supplies and other current assets	0.1
Estimated fair value of assets acquired	$ 23.6

The fair value of equity method investments included in the purchase price allocation.

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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.

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Amount of assets acquired at the acquisition date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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