XML 52 R41.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Income Taxes (Details) $ in Millions | 3 Months Ended
--- | ---
Dec. 31, 2017 USD ($)
Income Tax Disclosure [Abstract] |
Tax benefit related to tax cuts and jobs act | $ 11.3

X
- Definition Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax(Expense) Benefit + References No definition available. + Details
Name: | alco_TaxCutsandJobsActof2017IncompleteAccountingChangeinTaxRateDeferredTaxLiabilityProvisionalIncomeTaxExpenseBenefit
Namespace Prefix: | alco_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration