Cash Dividends - Additional Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	1 Months Ended	0 Months Ended
Mar. 10, 2014	Apr. 19, 2013	Mar. 11, 2013	Apr. 18, 2014 Subsequent Event
Dividends [Line Items]
Cash dividend declared	$ 0.05		$ 0.07
Dividend distributed date	Apr. 18, 2014		Apr. 19, 2013
Cash dividend record date	Apr. 04, 2014		Apr. 05, 2013
Cash dividends paid		$ 1,976		$ 1,417

Cash dividend paid.

No definition available.

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

- Details

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Namespace Prefix:	avd_
Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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