Name:	alex_AdditionalWatershedLandsAccessibleByLicenses
Namespace Prefix:	alex_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

The approximate percentage of irrigation water used by HC and S over the last ten years provided by the West Maui irrigation system.

No definition available.

Name:	alex_ApproximatePercentageOfIrrigationWaterProvidedByWestMauiIrrigationSystem
Namespace Prefix:	alex_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The capacity of irrigation water used by HC and S supplied by the additional watershed lands over the last ten years.

No definition available.

Name:	alex_CapacityOfIrrigationWaterSuppliedByAdditionalWatershedLands
Namespace Prefix:	alex_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Maximum potential amount of future payments (undiscounted) the Company could be required to make to a surety or lender, from whom the company obtained a bond or letter of credit, if the Company fails to perform and the surety or lender has made payment to the obligee or beneficiary.

No definition available.

Name:	alex_ContingentObligationsMaximumExposure
Namespace Prefix:	alex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The number of boilers impacted by the nationwide standards published by the EPA for controlling hazardous air pollutant emissions from industrial, commercial, and institutional boilers and process heaters.

No definition available.

Name:	alex_NumberOfBoilersImpactedByEpaStandards
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of organizations that filed a petition with the Water Commission to establish IIFS.

No definition available.

Name:	alex_NumberOfOrganizationsThatFiledPetitionToEstablishIifs
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of other farms involved in an employment lawsuit.

No definition available.

Name:	alex_NumberOfOtherFarmsInvolvedInEmploymentLawsuit
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of petitions on which the Water Commission to action, which resulted in some quantity of water being returned to the streams rather than being utilized for irrigation purposes, as per the IIFS request.

No definition available.

Name:	alex_NumberOfPetitionsOnWhichWaterCommissionTookAction
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of streams for which interim instream flow standards (IIFS) was requested via petitions filed by a third party to the Commission on Water Resource Management of the state of Hawaii.

No definition available.

Name:	alex_NumberOfStreamsForWhichIifsWasRequested
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of water licenses held by the entity, which provides access to another 30,000 acres owned by the State of Hawaii in East Maui. All of these licenses were extended as revocable permits that are renewed annually.

No definition available.

Name:	alex_NumberOfWaterLicensesHeldAndExtendedAsRevocablePermits
Namespace Prefix:	alex_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Period provided by the irrigation system for water use.

No definition available.

Name:	alex_PeriodProvidedByIrrigationSystem
Namespace Prefix:	alex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of acres of watershed lands in East Maui owned by the entity.

No definition available.

Name:	alex_WatershedLandsInEastMauiOwned
Namespace Prefix:	alex_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248