2.4.0.82414402 - Disclosure - Discontinued operations (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2QTDhttp://www.sec.gov/CIK0001035443duration2013-04-01T00:00:002013-06-30T00:00:00PropertyStandardhttp://www.are.com/20130630propertyare0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012Q2QTDhttp://www.sec.gov/CIK0001035443duration2012-04-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2013Q2YTDhttp://www.sec.gov/CIK0001035443duration2013-01-01T00:00:002013-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$D2012Q2YTDhttp://www.sec.gov/CIK0001035443duration2012-01-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5false USDfalsefalse$I2012Q4http://www.sec.gov/CIK0001035443instant2012-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 2us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Net assets of discontinued operations2false 3us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse41800004180USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse41800004180USD$falsetruefalse4falsefalsefalse00falsefalsefalse5truefalsefalse7644000076440USD$falsetruefalsexbrli:monetaryItemTypemonetaryFor the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760 false2Total liabilities6false 3are_NetAssetsOfDisposalGroupIncludingDiscontinuedOperationare_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse41790004179falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse41790004179falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse7775300077753falsefalsefalsexbrli:monetaryItemTypemonetaryRepresents the total assets less total liabilities for discontinued operations.No definition available.true2Net assets of discontinued operations7true 2us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Income from discontinued operations, net8false 3us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenueus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse241000241falsefalsefalse2truefalsefalse88310008831falsefalsefalse3truefalsefalse37370003737falsefalsefalse4truefalsefalse1813800018138falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph c -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 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 false2Total revenues9false 3us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingExpenseus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse217000217falsefalsefalse2truefalsefalse25060002506falsefalsefalse3truefalsefalse16290001629falsefalsefalse4truefalsefalse55490005549falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of operating expenses attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 false2Operating expenses10false 3us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse2400024falsefalsefalse2truefalsefalse63250006325falsefalsefalse3truefalsefalse21080002108falsefalsefalse4truefalsefalse1258900012589falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 true2Total revenues less operating expenses11false 3are_DiscontinuedOperationsDepreciationExpenseare_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00falsefalsefalse2truefalsefalse16140001614falsefalsefalse3truefalsefalse930000930falsefalsefalse4truefalsefalse32330003233falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of depreciation expense attributable to discontinued operations, during the reporting period.No definition available.false2Depreciation expense12false 3us-gaap_GainLossOnDispositionOfRealEstateDiscontinuedOperationsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-219000-219falsefalsefalse2truefalsefalse-2000-2falsefalsefalse3truefalsefalse121000121falsefalsefalse4truefalsefalse-2000-2falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of difference between the carrying amount and the sales price of real estate properties sold as part of discontinued operations.No definition available.false2Loss (gain) on sale of real estate13false 3us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse243000243USD$falsetruefalse2truefalsefalse47130004713USD$falsetruefalse3truefalsefalse10570001057USD$falsetruefalse4truefalsefalse93580009358USD$falsetruefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. 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Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.12) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 13 -Article 7 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.14) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Article 5 true2Income from discontinued operations, net14false 2are_DisposalGroupIncludingDiscontinuedOperationOperatingPropertiesHeldForSaleNumberare_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse22falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerRepresents the number of operating properties which are classified as held for sale and which have been included in income (loss) from discontinued operations.No definition available.false256Number of operating properties classified as held for sale15false 2are_DisposalGroupIncludingDiscontinuedOperationPropertiesSoldNumberare_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1010falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerRepresents the number of properties sold during the period.No definition available.false256Number of properties soldfalseDiscontinued operations (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.are.com/role/DiscontinuedOperationsDetails515