The increase (decrease) during the reporting period in the obligation created by deferred compensation under acquisitions that will be paid in the future.

No definition available.

+ Details

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Namespace Prefix:	avd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		9 Months Ended
	Jul. 01, 2019	Jan. 10, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Reduction in deferred consideration balances			$ 651	$ 3,969	$ 3,539	$ 5,437
Payments made for business acquisitions	$ 7,293
Deferred consideration			1,400	$ 4,398	1,400	$ 4,398
Defensive and Agrovant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Reduction in deferred consideration balances			92		167
Payments made for business acquisitions		$ 20,679	$ 30		$ 838