Joint Ventures (Sales, Profit, and Income) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Net sales	$ 55,465	$ 54,597	$ 47,321
Gross profit	21,229	21,462	16,829
Net income	$ 11,002	$ 9,796	$ 8,292

The amount of net income (loss) reported by an equity method investment of the entity.

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