XML 13 R39.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Legal Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 1 Months Ended |
--- | --- | ---
Apr. 30, 2015 | Mar. 31, 2008 | Jan. 31, 2015
Loss Contingencies [Line Items] |  |  |
Payment received from proceeds deposited with bankruptcy court | $ 1.6 agx_BankruptcyClaimsAmountReceivedFromAmountOfClaimsRetainedByCourt |  |
GPS [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Net proceeds held by the bankruptcy court |  |  | 5.5 agx_BankruptcyClaimsAmountOfClaimsRetainedByCourt / dei_LegalEntityAxis = agx_GemmaPowerSystemsMember
GPS [Member] | Procurement and Construction Services Related to Nebraska Project [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
GPS mechanics lien against Nebraska project |  | $ 23.8 us-gaap_BankruptcyClaimsAmountOfClaimsFiled / dei_LegalEntityAxis = agx_GemmaPowerSystemsMember / us-gaap_LitigationCaseAxis = agx_ProcurementAndConstructionServicesRelatedToNebraskaProjectMember |

X
- Definition Bankruptcy claims amount of claims retained by court. + References No definition available. + Details
Name: | agx_BankruptcyClaimsAmountOfClaimsRetainedByCourt
Namespace Prefix: | agx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Bankruptcy claims amount received from amount of claims retained by court. + References No definition available. + Details
Name: | agx_BankruptcyClaimsAmountReceivedFromAmountOfClaimsRetainedByCourt
Namespace Prefix: | agx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of bankruptcy claim filed with bankruptcy court. + References No definition available. + Details
Name: | us-gaap_BankruptcyClaimsAmountOfClaimsFiled
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=agx_GemmaPowerSystemsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |