Quarterly report pursuant to Section 13 or 15(d)

Property, Buildings and Equipment, Net (Details)

v2.4.1.9
Property, Buildings and Equipment, Net (Details) (USD $)
3 Months Ended 6 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2015
Mar. 31, 2014
Apr. 03, 2015
Sep. 30, 2014
Sep. 04, 2014
Property, Plant and Equipment [Line Items]              
Net property, buildings and equipment $ 383,446,000us-gaap_PropertyPlantAndEquipmentNet   $ 383,446,000us-gaap_PropertyPlantAndEquipmentNet     $ 126,833,000us-gaap_PropertyPlantAndEquipmentNet  
Impairment on assets held for sale 541,000us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf    541,000us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf         
Sales price         1,509,000us-gaap_SignificantAcquisitionsAndDisposalsAcquisitionCostsOrSaleProceeds    
Long-term debt 210,011,000us-gaap_LongTermDebt   210,011,000us-gaap_LongTermDebt     61,640,000us-gaap_LongTermDebt  
Citrus, Land and Land improvements [Member]              
Property, Plant and Equipment [Line Items]              
Impairment on assets held for sale     541,000us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf
/ us-gaap_LongLivedAssetsHeldForSaleByAssetTypeAxis
= alco_CitrusLandAndLandImprovementsMember
       
Silver Nip [Member]              
Property, Plant and Equipment [Line Items]              
Long-term debt             11,000,000us-gaap_LongTermDebt
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= alco_SilverNipMember
Depreciable Property Plant and Equipment [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 332,597,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
  332,597,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
    150,192,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
 
Less accumulated depreciation and depletion (72,158,000)us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
  (72,158,000)us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
    (63,031,000)us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
 
Net property, buildings and equipment 260,439,000us-gaap_PropertyPlantAndEquipmentNet
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
  260,439,000us-gaap_PropertyPlantAndEquipmentNet
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
    87,161,000us-gaap_PropertyPlantAndEquipmentNet
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_DepreciablePropertyPlantAndEquipmentMember
 
Breeding herd [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 10,897,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BreedingAndProductionAnimalsMember
  10,897,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BreedingAndProductionAnimalsMember
    11,558,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BreedingAndProductionAnimalsMember
 
Buildings [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 21,010,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BuildingMember
  21,010,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BuildingMember
    16,052,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_BuildingMember
 
Citrus trees [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 242,278,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_CitrusTreesMember
  242,278,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_CitrusTreesMember
    66,886,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= alco_CitrusTreesMember
 
Equipment and Other Facilities [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 58,412,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_MachineryAndEquipmentMember
  58,412,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_MachineryAndEquipmentMember
    55,696,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_MachineryAndEquipmentMember
 
Land and Land Improvements [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment 123,007,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
  123,007,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
    39,672,000us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
 
Land and Land Improvements [Member] | Silver Nip [Member]              
Property, Plant and Equipment [Line Items]              
Area of land acquired             1,500alco_SignificantAcquisitionsAndDisposalsAreaOfLand
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= alco_SilverNipMember
Sales price             17,600,000us-gaap_SignificantAcquisitionsAndDisposalsAcquisitionCostsOrSaleProceeds
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= alco_SilverNipMember
Land and Land Improvements [Member] | Silver Nip [Member] | Citrus, Land and Land improvements [Member]              
Property, Plant and Equipment [Line Items]              
Gross property, buildings and equipment           2,832,159us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_LongLivedAssetsHeldForSaleByAssetTypeAxis
= alco_CitrusLandAndLandImprovementsMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= alco_SilverNipMember
 
Pre-tax gains on sale of properties     $ 2,926,553us-gaap_GainLossOnSaleOfPropertyPlantEquipment
/ us-gaap_LongLivedAssetsHeldForSaleByAssetTypeAxis
= alco_CitrusLandAndLandImprovementsMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LandAndLandImprovementsMember
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= alco_SilverNipMember