2.2.0.25truefalse0110 - Statement - Consolidated Balance SheetstruefalseIn Thousandsfalse1falsefalseUSDfalsefalse12/31/2010 USD ($) $BalanceAsOf_31Dec2010http://www.sec.gov/CIK0000921112instant2010-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse12/31/2009 USD ($) $BalanceAsOf_31Dec2009http://www.sec.gov/CIK0000921112instant2009-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0lry_RealEstateAbstractlryfalsenadurationReal Estate Abstract.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringReal Estate Abstract.falsefalseReal estate:3false0lry_LandAndLandImprovementslryfalsedebitinstantAggregate of the carrying amounts as of the balance sheet date of investments in land and land improvements included in...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse864797000864797falsetruefalsefalsefalse2truefalsefalse848988000848988falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate of the carrying amounts as of the balance sheet date of investments in land and land improvements included in operating real estate.No authoritative reference available.falsefalseLand and land improvements4false0us-gaap_InvestmentBuildingAndBuildingImprovementsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse44206620004420662falsefalsefalsefalsefalse2truefalsefalse42832500004283250falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.No authoritative reference available.falsefalseBuilding and improvements5false0us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciationus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegatedtotal1truefalsefalse-1090685000-1090685falsefalsefalsefalsefalse2truefalsefalse-970935000-970935falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cumulative amount of depreciation for real estate property held for investment purposes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 7 truefalseLess accumulated depreciation6false0lry_OperatingRealEstatelryfalsedebitinstantSum of the carrying amounts as of the balance sheet date of all operating real estate assets.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse41947740004194774falsefalsefalsefalsefalse2truefalsefalse41613030004161303falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all operating real estate assets.No authoritative reference available.falsefalseOperating real estate7false0us-gaap_DevelopmentInProcessus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse6671400066714falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe current amount of expenditures for a real estate project that has not yet been completed.No authoritative reference available.falsefalseDevelopment in progress8false0us-gaap_LandAvailableForDevelopmentus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse209253000209253falsefalsefalsefalsefalse2truefalsefalse218633000218633falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount of land available for development.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph d -Article 7 truefalseLand held for development9false0us-gaap_RealEstateInvestmentPropertyNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse44040270004404027falsefalsefalsefalsefalse2truefalsefalse44466500004446650falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe net book value of real estate property held for investment purposes.No authoritative reference available.falsefalseNet real estate10false0us-gaap_CashAndCashEquivalentsAtCarryingValueus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse108409000108409falsefalsefalsefalsefalse2truefalsefalse237446000237446falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncludes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 falsefalseCash and cash equivalents11false0us-gaap_RestrictedCashAndCashEquivalentsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse4952600049526falsefalsefalsefalsefalse2truefalsefalse4223200042232falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Chapter 4 -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 falsefalseRestricted cash12false0us-gaap_AccountsReceivableNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse68980006898falsefalsefalsefalsefalse2truefalsefalse60570006057falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Article 5 falsefalseAccounts receivable13false0us-gaap_DeferredRentReceivablesNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse108933000108933falsefalsefalsefalsefalse2truefalsefalse9552700095527falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable should be reduced by allowances attributable to, for instance, credit risk associated with a lessee.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-3 -Paragraph 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 13 -Paragraph 19 -Subparagraph b falsefalseDeferred rent receivable14false0lry_DeferredFinancingAndLeasingCostsNetOfAccumulatedAmortizationlryfalsedebitinstantAggregate of the carrying amounts as of the balance sheet date of deferred financing and leasing costs, net of accumulated...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse141464000141464falsefalsefalsefalsefalse2truefalsefalse134309000134309falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate of the carrying amounts as of the balance sheet date of deferred financing and leasing costs, net of accumulated amortization.No authoritative reference available.falsefalseDeferred financing and leasing costs, net15false0us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVenturesus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse171916000171916falsefalsefalsefalsefalse2truefalsefalse175584000175584falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable form a party that is affiliated with the reporting entity by means of direct or indirect ownership.No authoritative reference available.falsefalseInvestments in and advances to unconsolidated joint ventures16false0us-gaap_AssetsHeldForSaleAtCarryingValueus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse55640005564falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRepresents the sum of the carrying value of all the Assets Held-for-Sale at the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph a falsefalseAssets held for sale17false0us-gaap_PrepaidExpenseAndOtherAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse7166000071660falsefalsefalsefalsefalse2truefalsefalse8557400085574falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amount for an unclassified balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs and the carrying amount as of the balance sheet date of assets not otherwise specified in the taxonomy. Also includes assets not individually reported in the financial statements, or not separately disclosed in notes.No authoritative reference available.truefalsePrepaid expenses and other assets18false0us-gaap_Assetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse50628330005062833falsefalsefalsefalsefalse2truefalsefalse52289430005228943falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 truefalseTotal assets19true0us-gaap_LiabilitiesAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLIABILITIES20false0us-gaap_NotesAndLoansPayableus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse320679000320679falsefalsefalsefalsefalse2truefalsefalse473993000473993falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 falsefalseMortgage loans21false0us-gaap_UnsecuredDebtus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse20391430002039143falsefalsefalsefalsefalse2truefalsefalse18428820001842882falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Article 5 -Subsection 19, 20, 22 falsefalseUnsecured notes22false0us-gaap_LineOfCreditFacilityAmountOutstandingus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse140000000140000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount borrowed under the credit facility as of the balance-sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseCredit facility23false0us-gaap_AccountsPayableCurrentAndNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse2365200023652falsefalsefalsefalsefalse2truefalsefalse3119500031195falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 falsefalseAccounts payable24false0us-gaap_InterestPayableCurrentAndNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse2982100029821falsefalsefalsefalsefalse2truefalsefalse3125100031251falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 falsefalseAccrued interest25false0us-gaap_DividendsPayableCurrentAndNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5614900056149falsefalsefalsefalsefalse2truefalsefalse5540200055402falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 falsefalseDividend and distributions payable26false0us-gaap_OtherLiabilitiesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse154837000154837falsefalsefalsefalsefalse2truefalsefalse171051000171051falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of liabilities not otherwise specified in the taxonomy. Also serves as the sum of liabilities not individually reported in the financial statements, or not separately disclosed in notes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Article 9 truefalseOther liabilities27false0us-gaap_Liabilitiesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse26242810002624281falsefalsefalsefalsefalse2truefalsefalse27457740002745774falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.No authoritative reference available.truefalseTotal liabilities28true0us-gaap_StockholdersEquityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLiberty Property Trust shareholders' equity29false0us-gaap_CommonStockValueus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse116000116falsefalsefalsefalsefalse2truefalsefalse114000114falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryDollar value of issued common stock whether issued at par value, no par or stated value. This item includes treasury stock repurchased by the entity. Note: elements for number of common shares, par value and other disclosure concepts are in another section within stockholders' equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 falsefalseCommon shares of beneficial interest, $.001 par value, 183,987,000 shares authorized; 115,530,608 (includes 1,249,909 in treasury) and 113,875,211 (includes 1,249,909 in treasury) shares issued and outstanding as of December 31, 2010 and 2009, respectively30false0us-gaap_AdditionalPaidInCapitalus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse25601930002560193falsefalsefalsefalsefalse2truefalsefalse25097040002509704falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExcess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of APIC associated with common AND preferred stock. For APIC associated with only common stock, use the element Additional Paid In Capital, Common Stock. For APIC associated with only preferred stock, use the element Additional Paid In Capital, Preferred Stock.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 falsefalseAdditional paid-in capital31false0us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-155000-155falsefalsefalsefalsefalse2truefalsefalse23390002339falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAccumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at fiscal year-end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, and unrealized gains and losses on certain investments in debt and equity securities as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 14, 17, 26 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 falsefalseAccumulated other comprehensive (loss) income32false0us-gaap_AccumulatedDistributionsInExcessOfNetIncomeus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-426017000-426017falsefalsefalsefalsefalse2truefalsefalse-337911000-337911falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe amount as of the balance sheet date by which cumulative distributions to shareholders (or partners) exceed retained earnings (or accumulated earnings).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 93-2 -Paragraph 13 -Subparagraph b falsefalseDistributions in excess of net income33false0us-gaap_TreasuryStockValueus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegatedtotal1truefalsefalse-51951000-51951falsefalsefalsefalsefalse2truefalsefalse-51951000-51951falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryValue of common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. Treasury stock is issued but is not outstanding. This stock has no voting rights and receives no dividends. Note that treasury stock may be recorded at its total cost or separately as par (or stated) value and additional paid in capital. Note: number of treasury shares concept is in another section within stockholders' equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-6 -Paragraph 3 truefalseCommon shares in treasury, at cost, 1,249,909 shares as of December 31, 2010 and 200934false0us-gaap_StockholdersEquityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse20821860002082186falsefalsefalsefalsefalse2truefalsefalse21222950002122295falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of all Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section E Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 falsefalseTotal Liberty Property Trust shareholders' equity36true0us-gaap_LimitedPartnersCapitalAccountAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLimited partners' equity37false0lry_MinorityInterestInRealEstateJointVentureslryfalsecreditinstantCarrying amount of the equity interests owned by external partners in joint ventures included in the entity's consolidated...falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse786000786falsefalsefalsefalsefalse2truefalsefalse621000621falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount of the equity interests owned by external partners in joint ventures included in the entity's consolidated financial statements.No authoritative reference available.truefalseNoncontrolling interest - consolidated joint ventures38false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse24385520002438552falsefalsefalsefalsefalse2truefalsefalse24831690002483169falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A truefalseTotal equity39false0us-gaap_LiabilitiesAndStockholdersEquityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse50628330005062833falsefalsefalsefalsefalse2truefalsefalse52289430005228943falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of all Liabilities and Stockholders' Equity items.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 32 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 25 -Article 7 truefalseTotal liabilities and equity40false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://libertyproperty.com/role/balancesheets1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{dei_LegalEntityAxis} : LIBERTY PROPERTY LIMITED PARTNERSHIP {us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Limited_Partnership_Member_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2010-12-31T00:00:000001-01-01T00:00:00falsefalselry_LimitedPartnershipMemberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldilry_LimitedPartnershipMemberdei_LegalEntityAxisexplicitMemberfalsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falsefalseUSDtruefalse{dei_LegalEntityAxis} : LIBERTY PROPERTY LIMITED PARTNERSHIP {us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2009 USD ($) $BalanceAsOf_31Dec2009_Limited_Partnership_Member_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2009-12-31T00:00:000001-01-01T00:00:00falsefalselry_LimitedPartnershipMemberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldilry_LimitedPartnershipMemberdei_LegalEntityAxisexplicitMemberfalsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseLIBERTY PROPERTY LIMITED PARTNERSHIP | Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively45true0us-gaap_LimitedPartnersCapitalAccountAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLimited partners' equity46false0us-gaap_LimitedPartnersCapitalAccountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6762100067621falsefalsefalsefalsefalse2truefalsefalse7229400072294falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe limited partner's ownership share in the capital account balance. The limited partners are partners of a publicly traded limited partnership or master limited partnership. Limited partners have limited liability and do not manage the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section F Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 2, 10, 15 falsefalseLimited partners' equity47false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse6762100067621falsefalsefalsefalsefalse2truefalsefalse7229400072294falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. 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This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A truefalseTotal equity48false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://libertyproperty.com/role/balancesheets1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse7falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2009 USD ($) $BalanceAsOf_31Dec2009_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$9falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2008 USD ($) $BalanceAsOf_31Dec2008_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2008-12-31T00:00:000001-01-01T00:00:00falsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$10falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Common units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively 12/31/2007 USD ($) $BalanceAsOf_31Dec2007_Common_Stock_Memberhttp://www.sec.gov/CIK0000921112instant2007-12-31T00:00:000001-01-01T00:00:00falsefalseus-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommonStockMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseCommon units; 3,928,733 and 4,011,354 outstanding as of December 31, 2010 and 2009, respectively52true0lry_NoncontrollingInterestOperatingPartnershipAbstractlryfalsenadurationNoncontrolling interest - operating partnership.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNoncontrolling interest - operating partnership.falsefalseNoncontrolling interest - operating partnership53false0us-gaap_MinorityInterestInOperatingPartnershipsus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6762100067621falsefalsefalsefalsefalse2truefalsefalse7229400072294falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount of the equity interests owned by noncontrolling partners in an operating partnership included in the entity's consolidated financial statements.No authoritative reference available.falsefalseNoncontrolling interest - operating partnership54true0us-gaap_LimitedPartnersCapitalAccountAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLimited partners' equity55false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse116000116falsefalsefalsefalsefalse2truefalsefalse114000114falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. 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This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A truefalseTotal equity64false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://libertyproperty.com/role/balancesheets1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse13falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Preferred units; 9,740,000 outstanding as of December 31, 2010 and 2009 12/31/2010 USD ($) 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It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 falsefalseCash and cash equivalents81false0us-gaap_RestrictedCashAndCashEquivalentsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse4952600049526falsefalsefalsefalsefalse2truefalsefalse4223200042232falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Chapter 4 -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 falsefalseRestricted cash82false0us-gaap_AccountsReceivableNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse68980006898falsefalsefalsefalsefalse2truefalsefalse60570006057falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Article 5 falsefalseAccounts receivable83false0us-gaap_DeferredRentReceivablesNetus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse108933000108933falsefalsefalsefalsefalse2truefalsefalse9552700095527falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable should be reduced by allowances attributable to, for instance, credit risk associated with a lessee.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-3 -Paragraph 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 13 -Paragraph 19 -Subparagraph b falsefalseDeferred rent receivable84false0lry_DeferredFinancingAndLeasingCostsNetOfAccumulatedAmortizationlryfalsedebitinstantAggregate of the carrying amounts as of the balance sheet date of deferred financing and leasing costs, net of accumulated...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse141464000141464falsefalsefalsefalsefalse2truefalsefalse134309000134309falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAggregate of the carrying amounts as of the balance sheet date of deferred financing and leasing costs, net of accumulated amortization.No authoritative reference available.falsefalseDeferred financing and leasing costs, net85false0us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVenturesus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse171916000171916falsefalsefalsefalsefalse2truefalsefalse175584000175584falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable form a party that is affiliated with the reporting entity by means of direct or indirect ownership.No authoritative reference available.falsefalseInvestments in and advances to unconsolidated joint ventures86false0us-gaap_AssetsHeldForSaleAtCarryingValueus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse55640005564falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRepresents the sum of the carrying value of all the Assets Held-for-Sale at the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph a falsefalseAssets held for sale87false0us-gaap_PrepaidExpenseAndOtherAssetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse7166000071660falsefalsefalsefalsefalse2truefalsefalse8557400085574falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amount for an unclassified balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs and the carrying amount as of the balance sheet date of assets not otherwise specified in the taxonomy. Also includes assets not individually reported in the financial statements, or not separately disclosed in notes.No authoritative reference available.truefalsePrepaid expenses and other assets88false0us-gaap_Assetsus-gaaptruedebitinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse50628330005062833falsefalsefalsefalsefalse2truefalsefalse52289430005228943falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 truefalseTotal assets89true0us-gaap_LiabilitiesAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLIABILITIES90false0us-gaap_NotesAndLoansPayableus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse320679000320679falsefalsefalsefalsefalse2truefalsefalse473993000473993falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 falsefalseMortgage loans91false0us-gaap_UnsecuredDebtus-gaaptruecreditinstantNo definition 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Also serves as the sum of liabilities not individually reported in the financial statements, or not separately disclosed in notes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Article 9 truefalseOther liabilities97false0us-gaap_Liabilitiesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse26242810002624281falsefalsefalsefalsefalse2truefalsefalse27457740002745774falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.No authoritative reference available.truefalseTotal liabilities99true0lry_NoncontrollingInterestOperatingPartnershipAbstractlryfalsenadurationNoncontrolling interest - operating partnership.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNoncontrolling interest - operating partnership.falsefalseNoncontrolling interest - operating partnership100false0us-gaap_GeneralPartnersCapitalAccountValueus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse20821860002082186falsefalsefalsefalsefalse2truefalsefalse21222950002122295falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCapital contributed by the general partner. The general partner is a partner of a publicly traded limited partnership or master limited partnership who has unlimited liability and manages the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section F Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 falsefalseGeneral partner's equity - common units, 115,530,608 and 113,875,211 units outstanding as of December 31, 2010 and December 31, 2009, respectively101true0us-gaap_LimitedPartnersCapitalAccountAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseLimited partners' equity102false0lry_MinorityInterestInRealEstateJointVentureslryfalsecreditinstantCarrying amount of the equity interests owned by external partners in joint ventures included in the entity's consolidated...falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse786000786falsefalsefalsefalsefalse2truefalsefalse621000621falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount of the equity interests owned by external partners in joint ventures included in the entity's consolidated financial statements.No authoritative reference available.truefalseNoncontrolling interest - consolidated joint ventures103false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse24385520002438552falsefalsefalsefalsefalse2truefalsefalse24831690002483169falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A truefalseTotal equity104false0us-gaap_LiabilitiesAndStockholdersEquityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse50628330005062833falsetruefalsefalsefalse2truefalsefalse52289430005228943falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of all Liabilities and Stockholders' Equity items.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 32 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 25 -Article 7 truefalseTotal liabilities and equity286Consolidated Balance Sheets (USD $)ThousandsUnKnownUnKnownUnKnownfalsetrue