Provision charged for the period based on estimated losses to be realized from rent transactions.

No definition available.

Name:	are_AllowanceForEstimatedLossesRelatedToTenantRent
Namespace Prefix:	are_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	are_BasisOfPresentationAbstract
Namespace Prefix:	are_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the standard deposit insurance coverage provided by the Federal Deposit Insurance Corporation.

+ References

No definition available.

+ Details

Name:	are_ConcentrationRiskFDICInsuranceCoverage
Namespace Prefix:	are_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The percentage of ownership of common stock, less than ten percent in the investee accounted for under the cost method of accounting.

+ References

No definition available.

+ Details

Name:	are_CostMethodInvestmentOwnershipPercentage
Namespace Prefix:	are_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the maximum period within which sale of property is expected to be completed.

+ References

No definition available.

+ Details

Name:	are_MaximumExpectedPeriodOfSaleOfProperty
Namespace Prefix:	are_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of leases containing effective annual rent escalations.

+ References

No definition available.

+ Details

Name:	are_PercentageOfLeasesContainingEffectiveAnnualRentEscalation
Namespace Prefix:	are_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of leases that provided for the recapture of certain capital expenditures.

+ References

No definition available.

+ Details

Name:	are_PercentageOfLeasesProvidingForRecaptureOfCapitalExpenditures
Namespace Prefix:	are_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value of the assets acquired, the liabilities assumed, and any noncontrolling interests are recognized when an acquisition is of less than this percentage of interest and the acquisition constitutes a change in control of the acquired entity.

+ References

No definition available.

+ Details

Name:	are_PercentageOfOwnershipInterestCriteria
Namespace Prefix:	are_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of leases which are triple net leases.

+ References

No definition available.

+ Details

Name:	are_TripleNetLeasesPercentage
Namespace Prefix:	are_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Interest generated from day to day operating activities of the business. This element represents a revenue generating activity and is therefore gross (before any related cost of revenue items).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

+ Details

Name:	us-gaap_InterestIncomeOperating
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Basis of presentation and summary of significant accounting policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basis of presentation
Maximum expected period of sale of property (in years)	1 year
FDIC insurance coverage	$ 250,000
Cost method investment ownership percentage	10.00%	10.00%
Allowance for estimated losses	0	0
Percentage of leases which are triple net leases	94.00%
Percentage of leases containing effective annual rent escalations	95.00%
Percentage of leases providing for recapture of certain capital expenditures	92.00%
Interest income included in other income	$ 4,600,000	$ 3,400,000	$ 900,000
Maximum
Basis of presentation
Percentage of ownership interest criteria	100.00%
Land improvements
Property, plant and equipment depreciated on a straight-line basis using an estimated life
Estimated useful life	20 years
Buildings and building improvements \| Maximum
Property, plant and equipment depreciated on a straight-line basis using an estimated life
Estimated useful life	40 years
CANADA
Basis of presentation
Number of operating properties	5
CHINA
Basis of presentation
Number of operating properties	2
INDIA
Basis of presentation
Number of operating properties	5