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Earnings Before Income Tax Goal Weighted Percentage

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Market price performance measure targeted percentage.

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Net Sales Goal Weighted Percentage

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Share based compensation arrangement by share based payment award equity instruments other than options additional grants based on performance.

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Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other Than Options, Vesting Date

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Share Based Compensation Arrangements Maximum Target

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of noncash expense for share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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Gross number of share options (or share units) granted during the period.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Percentage of vesting of award under share-based payment arrangement.

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Number of new stock issued during the period.

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Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 2,164,000			$ 1,457,000			$ 5,159,000	$ 4,235,000
Performance Based Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted							0	0
Incentive Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees options granted	0						0
Common Stock Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested	3,685	32,771	105,582	17,591	20,313	8,800
Weighted Average Grant-Date Fair Value, Granted	$ 0	$ 13.34	$ 17.34	$ 0	$ 23.66	$ 19.97
Stock-based compensation	$ 1,082,000			$ 870,000			$ 2,751,000	$ 2,427,000
Unamortized Stock-Based Compensation	$ 6,849,000			$ 5,949,000			$ 6,849,000	$ 5,949,000
Remaining Weighted Average Period (years)							2 years	2 years
Number of Shares, Granted	0	40,522	297,679	0	22,308	254,972
Common Stock Grants \| Employee and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested								19,313
Number of shares expected to vest				19,760				19,760
Common Stock Grants \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant-Date Fair Value, Granted							$ 16.86	$ 20.27
Common Stock Grants \| Common Stock \| Employee and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued by equity investee							338,201	277,280
Common Stock Grants \| Vested immediately \| Employee and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested							31,771
Common Stock Grants \| Vesting Between 95 Days to 1,115 Days \| Employee and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares expected to vest	9,000						9,000
Common Stock Grants \| After One Year \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of days of service before cliff vesting							95 days	178 days
Common Stock Grants \| After One Year \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of days of service before cliff vesting							1115 days	1060 days
Common Stock Grants \| After Three Years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of days of service before cliff vesting							3 years	3 years
Common Stock Grants \| Three Equal Tranches \| Employee and Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares expected to vest	6,751						6,751
Unvested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized Stock-Based Compensation	$ 6,849,000						$ 6,849,000
Remaining Weighted Average Period (years)								2 years
Performance Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested	1,700		90,872	8,232		14,625
Weighted Average Grant-Date Fair Value, Granted			$ 16.96		$ 22.69	$ 18.79	$ 16.96	$ 18.74
Stock-based compensation	$ 977,000			$ 491,000			$ 2,108,000	$ 1,519,000
Unamortized Stock-Based Compensation	$ 3,320,000			$ 2,814,000			$ 3,320,000	$ 2,814,000
Remaining Weighted Average Period (years)							2 years	2 years
Number of Shares, Granted			137,557		3,850	122,446	137,557	130,332
Targeted performance percentage	200.00%			200.00%			200.00%	200.00%
Additional expenses recognized							$ 0
Number of Share, Additional granted based on performance	800		41,568	4,036			42,368
Performance Based Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target performance percentage to meet performance incentive stock options based on market							100.00%
Performance Based Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target performance percentage to meet performance incentive stock options based on market							125.00%
Performance Based Restricted Stock \| Vested on March 28, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting date							Mar. 28, 2022
Performance Based Restricted Stock \| Performance based stock options based upon financial performance of earnings before interest and tax ("EBIT") and net sales goal for the period commencing January 1, 2019 through December 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vesting based on Performance							80.00%
Earnings before income taxes goal weight, percentage							50.00%
Net sales goal weight, percentage							30.00%
Performance Based Restricted Stock \| Performance Based Shares Based Upon AVD Stock Price Appreciation Over the Course of the Period Commencing January 1, 2019 through December 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnings before income taxes goal weight, percentage							20.00%
Performance Based Restricted Stock \| Vested on March 9, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting date								Mar. 09, 2021
Performance Based Restricted Stock \| Performance based stock options based upon financial performance of earnings before interest and tax ("EBIT") and net sales goal for the period commencing January 1, 2018 and ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vesting based on Performance								80.00%
Earnings before income taxes goal weight, percentage								50.00%
Net sales goal weight, percentage								30.00%
Performance Based Restricted Stock \| Performance Based Shares Based Upon AVD Stock Price Appreciation Over the Course of the Period Commencing January 1, 2018 and ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Earnings before income taxes goal weight, percentage								20.00%
Performance Based Restricted Stock \| Performance Based Shares Related to Net Income Weighted at 50%, Net Sales Weighted at 30%, Commencing January 1, 2017 and Ending December 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant-Date Fair Value, Granted							$ 17.34
Performance Based Restricted Stock \| Remaining 20% of Performance Based Shares are Based Upon AVD Stock Price Appreciation for the Period Commencing January 1, 2017 and Ending December 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant-Date Fair Value, Granted							$ 15.46
Unvested Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized Stock-Based Compensation	$ 3,320,000						$ 3,320,000
Remaining Weighted Average Period (years)							2 years