The number of acres of additional watershed lands owned by the State of Hawaii in East Maui, which the entity can access using water licenses.

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- Definition

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

+ Details

Name:	alex_ApproximatePercentageOfIrrigationWaterProvidedByWestMauiIrrigationSystem
Namespace Prefix:	alex
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- Definition

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.

+ Details

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Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

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

+ Details

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

- Definition

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.

+ Details

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Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Letter of credit amount related to the entity's real estate business.

+ Details

Name:	alex_LetterOfCreditAmountRelatedToRealEstateBusiness
Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Letter of credit amount that enables the entity to qualify as a self-insurer for state and federal workers' compensation liabilities.

+ Details

Name:	alex_LetterOfCreditAmountThatEnablesQualificationAsSelfInsurer
Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ Details

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Namespace Prefix:	alex
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Period Type:	instant

- Definition

The number of farms in Hawaii, including the entity's subsidiary, against which a lawsuit was filed by the Equal Employment Opportunity Commission (EEOC) alleging that the farms were complicit in illegal acts by a company that had hired Thai workers for the farms.

+ Details

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- Definition

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.

+ Details

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Namespace Prefix:	alex
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Period Type:	instant

- Definition

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.

+ Details

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Namespace Prefix:	alex
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Balance Type:	na
Period Type:	instant

- Definition

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.

+ Details

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Namespace Prefix:	alex
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Balance Type:	na
Period Type:	instant

- Definition

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 letter of credit, if the Company fails to perform and the surety or lender has made payment to the obligee or beneficiary.

+ Details

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Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

+ Details

Name:	alex_UsCustomsBonds
Namespace Prefix:	alex
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ Details

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Namespace Prefix:	alex
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

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

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of a recognized obligation to a multiemployer plan in the event that the employer withdraws from the plan. In some situations, withdrawal from a multiemployer plan may result in an employer having an obligation to the plan for a portion of the unfunded benefit obligation of the pension plans and other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 13
-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.

+ Details

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Commitments, Guarantees and Contingencies (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011 Standby letters of credit [Member]	Jun. 30, 2011 Performance and customs bonds [Member]	Jun. 30, 2011 Guarantee of obligations of joint venture [Member]	Jun. 30, 2011 Benefit plan withdrawal obligations [Member]	Jun. 30, 2011 Long-term water lease request [Member]	May 31, 2010 Petitions filed requesting IIFS in East Maui streams [Member]	Sep. 25, 2008 Petitions filed requesting IIFS in East Maui streams [Member]	May 24, 2001 Petitions filed requesting IIFS in East Maui streams [Member]	Jun. 30, 2011 Petitions filed requesting IIFS in West Maui streams [Member]	Jun. 30, 2010 Petitions filed requesting IIFS in West Maui streams [Member]	Jun. 25, 2004 Petitions filed requesting IIFS in West Maui streams [Member]	Mar. 31, 2011 EPA standards for controlling emissions [Member]	Jun. 30, 2011 EEOC matter [Member]
Loss Contingencies [Line Items]
Contingent obligations, maximum exposure	$ 19	$ 31
Guarantor obligations, maximum exposure			10
Multiemployer plan withdrawal obligation				99
Letter of credit amount that enables qualification as self-insurer	8
Letter of credit amount related to real estate business	11
U.S. customs bonds		13
Bonds related to real estate construction projects		17
Bonds related to transportation and other matters		$ 1
Watershed lands in East Maui owned (in acres)					16,000
Number of water licenses held and extended as revocable permits					4
Additional watershed lands accessible by licenses (in acres)					30,000
Capacity of irrigation water supplied by additional watershed lands (in hundredths)					58.00%
Number of streams for which IIFS was requested								27			4
Number of petitions on which the Water Commission took action						19	8			2
Approximate percentage of irrigation water provided by the West Maui irrigation system (in hundredths)									15.00%
Number of boilers impacted by EPA standards												3
Number of farms alleged complicit in illegal acts													5