XML 87 R30.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Accounts Receivable (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |  |  | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 31, 2010 | Jul. 31, 2013 | Jan. 31, 2013 | Jul. 31, 2013 Maximum [Member] | Jul. 31, 2013 Minimum [Member] | Jul. 31, 2013 Construction contracts retainages [Member] | Jan. 31, 2013 Construction contracts retainages [Member]
Accounts Receivable (Textual) [Abstract] |  |  |  |  |  |  |
Contract payment amounts retained by project owners |  |  |  |  |  | $ 13.3 | $ 20.2
Length of retention period of amount given to project owners |  |  |  | 3 years | 9 months |  |
Accounts Receivable (Additional Textual) [Abstract] |  |  |  |  |  |  |
Allowance for doubtful accounts |  | 5.5 | 5.5 |  |  |  |
The amount of the net proceeds remaining from public auction of the partially completed project | $ 5.5 |  |  |  |  |  |

X
- Details
Name: | agx_AccountsReceivableAdditionalTextualAbstract
Namespace Prefix: | agx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | agx_AccountsReceivableTextualAbstract
Namespace Prefix: | agx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The length of time retainage amounts are held by project owners prior to payment to contractor. + References No definition available. + Details
Name: | agx_LengthOfRetentionPeriodOfAmountGivenToProjectOwners
Namespace Prefix: | agx_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 4 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of increase (decrease) in the allowance for doubtful accounts. + References No definition available. + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 910 -SubTopic 310 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49370-109356 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3(c)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Subparagraph c(1) -Article 5 + Details
Name: | us-gaap_ContractReceivableRetainage
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant