Summary of Business Sales by Product and Geographic Location (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net sales
Net sales	$ 104,555	$ 113,104	$ 200,517	$ 212,780
Change in net sales	104,555	$ (8,549)	200,517	$ (12,263)
Percentage change in net sales		(8.00%)		(6.00%)
Gross profit:
Gross profit	40,306	$ 41,653	78,687	$ 83,355
Change in gross profit	40,306	$ (1,347)	78,687	$ (4,668)
Percentage change in gross profit		(3.00%)		(6.00%)
US
Net sales
Net sales	58,542	$ 64,530	119,897	$ 126,067
Change in net sales	58,542	$ (5,988)	119,897	$ (6,170)
Percentage change in net sales		(9.00%)		(5.00%)
Gross profit:
Gross profit	28,787	$ 27,277	57,751	$ 57,086
Change in gross profit	28,787	$ 1,510	57,751	$ 665
Percentage change in gross profit		6.00%		1.00%
US \| Crop
Net sales
Net sales	44,670	$ 47,575	95,032	$ 97,845
Change in net sales	44,670	$ (2,905)	95,032	$ (2,813)
Percentage change in net sales		(6.00%)		(3.00%)
Gross profit:
Gross profit	21,758	$ 18,719	46,003	$ 42,214
Change in gross profit	21,758	$ 3,039	46,003	$ 3,789
Percentage change in gross profit		16.00%		9.00%
US \| Non-Crop
Net sales
Net sales	13,872	$ 16,955	24,865	$ 28,222
Change in net sales	13,872	$ (3,083)	24,865	$ (3,357)
Percentage change in net sales		(18.00%)		(12.00%)
Gross profit:
Gross profit	7,029	$ 8,558	11,748	$ 14,872
Change in gross profit	7,029	$ (1,529)	11,748	$ (3,124)
Percentage change in gross profit		(18.00%)		(21.00%)
International
Net sales
Net sales	46,013	$ 48,574	80,620	$ 86,713
Change in net sales	46,013	$ (2,561)	80,620	$ (6,093)
Percentage change in net sales		(5.00%)		(7.00%)
Gross profit:
Gross profit	11,519	$ 14,376	20,936	$ 26,269
Change in gross profit	$ 11,519	$ (2,857)	$ 20,936	$ (5,333)
Percentage change in gross profit		(20.00%)		(20.00%)