Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventory [Line Items]
Total LIFO inventories	$ 26,029	$ 28,546
LIFO [Member]
Inventory [Line Items]
Finished goods	23,486	29,686
Raw materials	21,344	20,231
Total FIFO (first-in,first-out) inventories	44,830	49,917
Reserve to adjust inventories to LIFO value	(21,371)	(21,371)
Total LIFO inventories	23,459	$ 28,546
FIFO [Member]
Inventory [Line Items]
Work-in-process	580
Raw materials	1,990
Total FIFO (first-in,first-out) inventories	$ 2,570

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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