Share-Based Compensation - Schedule of Compensation Cost for Cash-settled Restricted Stock (Details) - Cash-settled Restricted Stock - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total expense before income taxes	$ 1,445	$ 1,023	$ 3,672	$ 3,166
Income tax benefit	(158)	(175)	(368)	(557)
Total expense after income taxes	1,287	848	3,304	2,609
Cost of goods sold
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total expense before income taxes	381	327	896	963
Selling, general and administrative expenses
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total expense before income taxes	$ 1,064	$ 696	$ 2,776	$ 2,203

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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