2.4.0.82417402 - Disclosure - Subsequent Events (Details)truefalsefalse1false USDfalsefalse$D2013Q3SD_us-gaap_BusinessAcquisitionAxis_lry_CabotIndustrialValueFundIIIMember_us-gaap_SubsequentEventTypeAxis_us-gaap_SubsequentEventMemberhttp://www.sec.gov/CIK0000921112duration2013-07-30T00:00:002013-07-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170sqftStandardhttp://www.xbrl.org/2009/utrsqftutreg0USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse1false USDtruefalse$D2013Q3SD_us-gaap_BusinessAcquisitionAxis_lry_CabotIndustrialValueFundIIIMember_us-gaap_SubsequentEventTypeAxis_us-gaap_SubsequentEventMemberhttp://www.sec.gov/CIK0000921112duration2013-07-30T00:00:002013-07-31T00:00:00falsefalseSubsequent Event [Member]us-gaap_SubsequentEventTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SubsequentEventMemberus-gaap_SubsequentEventTypeAxisexplicitMemberfalsefalseCabot Industrial Value Fund III [Member]us-gaap_BusinessAcquisitionAxisxbrldihttp://xbrl.org/2006/xbrldilry_CabotIndustrialValueFundIIIMemberus-gaap_BusinessAcquisitionAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170sqftStandardhttp://www.xbrl.org/2009/utrsqftutreg0USDUSD$nanafalse0Subsequent Event [Member] | Cabot Industrial Value Fund III [Member]2true 3us-gaap_SubsequentEventLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Subsequent Event [Line Items]3false 4us-gaap_BusinessAcquisitionCostOfAcquiredEntityPurchasePriceus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse14750000001475000000USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 51 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. false2Business Acquisition, Cost of Acquired Entity, Purchase Price4false 4us-gaap_AreaOfRealEstatePropertyus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2300000023000000falsefalsefalsenum:areaItemTypedecimalArea of a real estate property.No definition available.false256Area of Real Estate Property5false 4us-gaap_NoncashOrPartNoncashAcquisitionDebtAssumed1us-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse230000000230000000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 false2Noncash or Part Noncash Acquisition, Debt Assumed6false 4us-gaap_BridgeLoanus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse12700000001270000000USD$falsetruefalsexbrli:monetaryItemTypemonetaryShort-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 false2Bridge LoanfalseSubsequent Events (Details) (Subsequent Event [Member], Cabot Industrial Value Fund III [Member], USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.libertyproperty.com/role/SubsequentEventsDetails16