Aggregate special dividends declared during the period for each share of common stock outstanding.

No definition available.

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Namespace Prefix:	agx_
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Period Type:	duration

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

+ Details

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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CASH DIVIDENDS (Details) - $ / shares	1 Months Ended			12 Months Ended
CASH DIVIDENDS (Details) - $ / shares	Sep. 30, 2016	Sep. 30, 2015	Jan. 31, 2015	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
CASH DIVIDENDS
Cash dividend declared per common share	$ 0.70	$ 0.70		$ 1.00	$ 0.70	$ 0.70
Dividend record date	Oct. 18, 2016
Special Cash dividend declared per common share	$ 0.30		$ 0.70
Special Cash dividend paid per common share						$ 0.70