Annual report pursuant to Section 13 and 15(d)

Segment Reporting (Schedule Of Reconciliation Of Net Operating Income To Income From Continuing Operations) (Details)

v2.4.1.9
Segment Reporting (Schedule Of Reconciliation Of Net Operating Income To Income From Continuing Operations) (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Segment Reporting [Abstract]                      
Net operating income                 $ 149,615cli_SegmentReportingInformationNetOperatingIncomeLossForReportableSegment [1] $ 204,089cli_SegmentReportingInformationNetOperatingIncomeLossForReportableSegment $ 226,704cli_SegmentReportingInformationNetOperatingIncomeLossForReportableSegment [1]
Depreciation and amortization (40,811)us-gaap_DepreciationAndAmortization (41,983)us-gaap_DepreciationAndAmortization (44,711)us-gaap_DepreciationAndAmortization (44,985)us-gaap_DepreciationAndAmortization (47,666)us-gaap_DepreciationAndAmortization (46,087)us-gaap_DepreciationAndAmortization (45,665)us-gaap_DepreciationAndAmortization (43,348)us-gaap_DepreciationAndAmortization (172,490)us-gaap_DepreciationAndAmortization (182,766)us-gaap_DepreciationAndAmortization (174,333)us-gaap_DepreciationAndAmortization
Realized gains on disposition of rental property, net   264us-gaap_GainLossOnDispositionOfAssets 54,584us-gaap_GainLossOnDispositionOfAssets           54,848us-gaap_GainLossOnDispositionOfAssets    
Loss from early extinguishment of debt (582)us-gaap_GainsLossesOnExtinguishmentOfDebt       (156)us-gaap_GainsLossesOnExtinguishmentOfDebt       (582)us-gaap_GainsLossesOnExtinguishmentOfDebt (156)us-gaap_GainsLossesOnExtinguishmentOfDebt (4,960)us-gaap_GainsLossesOnExtinguishmentOfDebt
Impairments         (62,153)us-gaap_AssetImpairmentCharges [2],[3] (48,700)us-gaap_AssetImpairmentCharges [2]       (110,853)us-gaap_AssetImpairmentCharges (9,845)us-gaap_AssetImpairmentCharges
Income (loss) from continuing operations (10,413)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 2,085us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 57,347us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest (17,628)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest (60,202)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest (46,039)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 8,599us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 7,956us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 31,391us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest (89,686)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest 37,566us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
Income from discontinued operations         (9)us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax 2,157us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax 4,530us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax 5,133us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax   11,811us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax 21,878us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax
Loss from early extinguishment of debt             (703)cli_DiscontinuedOperationGainsLossesOnExtinguishmentOfDebt     (703)cli_DiscontinuedOperationGainsLossesOnExtinguishmentOfDebt  
Realized gains on disposition of rental property, net         (1,559)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax [4] 47,321us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax 13,758us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax     59,520us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax (13,175)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
Total discontinued operations, net         (1,568)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax 49,478us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax 17,585us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax 5,133us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax   70,628us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax 8,703us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax
Net income (loss) (10,413)us-gaap_ProfitLoss 2,085us-gaap_ProfitLoss 57,347us-gaap_ProfitLoss (17,628)us-gaap_ProfitLoss (61,770)us-gaap_ProfitLoss 3,439us-gaap_ProfitLoss 26,184us-gaap_ProfitLoss 13,089us-gaap_ProfitLoss 31,391us-gaap_ProfitLoss (19,058)us-gaap_ProfitLoss 46,269us-gaap_ProfitLoss
Noncontrolling interest in consolidated joint ventures 21us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 145us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 290us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 322us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 237us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 1,838us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 62us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 62us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 778us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 2,199us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable 330us-gaap_NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable
Noncontrolling interest in Operating Partnership 1,152us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (248)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (6,514)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable 2,008us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable 7,167us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable 5,313us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (1,048)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (973)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (3,602)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable 10,459us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable (4,619)us-gaap_NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable
Noncontrolling interest in discontinued operations         187cli_NoncontrollingInterestInDiscontinuedOperations (5,947)cli_NoncontrollingInterestInDiscontinuedOperations (2,127)cli_NoncontrollingInterestInDiscontinuedOperations (622)cli_NoncontrollingInterestInDiscontinuedOperations   (8,509)cli_NoncontrollingInterestInDiscontinuedOperations (1,058)cli_NoncontrollingInterestInDiscontinuedOperations
Net income (loss) available to common shareholders $ (9,240)us-gaap_NetIncomeLoss $ 1,982us-gaap_NetIncomeLoss $ 51,123us-gaap_NetIncomeLoss $ (15,298)us-gaap_NetIncomeLoss $ (54,179)us-gaap_NetIncomeLoss $ 4,643us-gaap_NetIncomeLoss $ 23,071us-gaap_NetIncomeLoss $ 11,556us-gaap_NetIncomeLoss $ 28,567us-gaap_NetIncomeLoss $ (14,909)us-gaap_NetIncomeLoss $ 40,922us-gaap_NetIncomeLoss
[1] Net operating income represents total revenues less total operating and interest expenses (as defined in Note “a”), plus equity in earnings (loss) of unconsolidated joint ventures, for the period.
[2] Amounts for the year ended December 31, 2013 relate to impairment charges as further described in Note 3: Real Estate Transactions - Impairments on Properties Held and Used.
[3] During the quarter ended December 31, 2013, the Company identified and recorded an out-of-period adjustment to reflect a charge of $1,260,000 to correct an error in the measurement of its impairment charges on certain properties in the third quarter of 2013. In the third quarter, in measuring the impairments on these properties, the Company did not include certain tenant improvement amounts to be paid for in-place leases in its discounted cash flows used to measure fair value and, as a result, should have recognized larger impairment charges by this aggregate amount. The Company has determined that this adjustment was not material to the quarter ended December 31, 2013 or the prior interim period.
[4] During the quarter ended December 31, 2013, the Company identified and recorded an out-of-period adjustment to reflect a charge of $1,559,000 to correct an error in its calculation of the gain on sale of rental property on a transaction that closed in the third quarter of 2013. In the third quarter, in recording the gain on the sale transaction, the Company did not include the full consolidated carrying amount of the property in computing the gain and, as a result, should have recognized a smaller gain by this amount. The Company has determined that this adjustment was not material to the quarter ended December 31, 2013 or the prior interim period.