XML 143 R71.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Treasury Stock - Schedule of Treasury Stock Purchases (Details) - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 29, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
Stockholders' Equity Note [Abstract] |  |  |  |
Total Number of Shares Purchased (in shares) |  | 72,266 | 104,145 | 78,446
Average Price Paid Per Share (in dollars per share) |  | $ 30.65 | $ 29.42 | $ 40.04
Total Shares Purchased as Part of Publicly Announced Plan or Program (in shares) |  | 722,406 | 650,140 | 545,995
Total Dollar Value of Shares Purchased | $ 1,676,443 | $ 2,214,756 | $ 3,064,000 | $ 3,141,000

X
- Definition Cumulative Treasury Stock Acquired As Part Of Program. + References No definition available. + Details
Name: | alco_CumulativeTreasuryStockAcquiredAsPartOfProgram
Namespace Prefix: | alco_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

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

X
- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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
Name: | us-gaap_TreasuryStockValueAcquiredCostMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration