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Concentration Risk, Percentage Concentration Risk, Percentage Tax Status of Dividends [Abstract] Tax Status of Dividends [Abstract] Common stock/unit per share Common Stock, Dividends, Per Share, Declared Allocation of Dividends, Ordinary Income Allocation of Dividends, Ordinary Income Allocation of Dividends, Ordinary Income Allocation of Dividends, Capital Gain Allocation of Dividends, Capital Gain Allocation of Dividends, Capital Gain Allocation of Dividends, Return of Capital Allocation of Dividends, Return of Capital Allocation of Dividends, Return of Capital Allocation of Dividends, Qualified Dividend Income Allocation of Dividends, Qualified Dividend Income Allocation of Dividends, Qualified Dividend Income - tax treatment of dividends Income Statement [Abstract] Statement [Table] Statement [Table] Partnership Interest [Member] Partnership Interest [Member] Parent Company [Member] Parent Company [Member] Statement [Line Items] Statement [Line Items] Interest Income Interest 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El Cerrito Plaza [Member] El Norte Parkway Plaza [Member] El Norte Pkwy Plaza [Member] El Norte Pkwy Plaza [Member] Encina Grande [Member] Encina Grande [Member] Encina Grande [Member] Fairfax Shopping Center [Member] Fairfax Shopping Center [Member] Fairfax Shopping Center [Member] Fairfield [Member] Fairfield [Member] Fairfield [Member] Falcon [Member] Falcon [Member] Falcon [Member] Fellsway Plaza [Member] Fellsway Plaza [Member] Fellsway Plaza [Member] Fenton Marketplace [Member] Fenton Marketplace [Member] Fenton Marketplace [Member] Fleming Island [Member] Fleming Island [Member] Fleming Island [Member] Fountain Square [Member] Fountain Square [Member] Fountain Square [Member] French Valley Village Center [Member] French Valley Village Center [Member] French Valley Village Center [Member] Friars Mission Center [Member] Friars Mission Center [Member] Friars Mission Center [Member] Garden City [Member] Garden City [Member] Garden City [Member] Gardens Square [Member] Gardens Square [Member] Gardens Square [Member] Gateway 101 [Member] Gateway 101 [Member] Gateway 101 [Member] Gateway Shopping Center [Member] Gateway Shopping Center [Member] Gateway Shopping Center [Member] Gelson's Westlake Market Plaza [Member] Gelson's Westlake Market Plaza [Member] Gelson's Westlake Market Plaza [Member] Glen Oak Plaza [Member] Glen Oak Plaza [Member] Glen Oak Plaza [Member] Glenwood Village [Member] Glenwood Village [Member] Glenwood Village [Member] Golden Hills Plaza [Member] Golden Hills Plaza [Member] Golden Hills Plaza [Member] Grand Ridge Plaza [Member] Grand Ridge Plaza [Member] Grand Ridge Plaza [Member] Hancock [Member] Hancock [Member] Hancock [Member] Harpeth Village Fieldstone [Member] Harpeth Village Fieldstone [Member] Harpeth Village Fieldstone [Member] Harris Crossing [Member] Harris Crossing [Member] Harris Crossing [Member] Heritage Land [Member] Heritage Land [Member] Heritage Land [Member] Heritage Plaza [Member] Heritage Plaza [Member] Heritage Plaza [Member] Hershey [Member] Hershey [Member] Hershey [Member] Hibernia Pavilion [Member] Hibernia Pavilion [Member] Hibernia Pavilion [Member] Hickory Creek Plaza [Member] Hickory Creek Plaza [Member] Hickory Creek Plaza [Member] Hillcrest Village [Member] Hillcrest Village [Member] Hillcrest Village [Member] Hilltop Village [Member] Hilltop Village [Member] Hilltop Village [Member] Hinsdale [Member] Hinsdale [Member] Hinsdale [Member] Holly Park [Member] Holly Park [Member] Holly Park [Member] Howell Mill Village [Member] Howell Mill Village [Member] Howell Mill Village [Member] Hyde Park [Member] Hyde Park [Member] Hyde Park [Member] Indian Springs [Member] Indian Springs [Member] Indian Springs [Member] Indio Towne Center [Member] Indio Towne Center [Member] Indio Towne Center [Member] Inglewood Plaza [Member] Inglewood Plaza [Member] Inglewood Plaza [Member] Jefferson Square [Member] Jefferson Square [Member] Jefferson Square [Member] Keller Town Center [Member] Keller Town Center [Member] Keller Town Center [Member] Kent Place [Member] Kent Place [Member] Kent Place [Member] Kirkwood Commons [Member] Kirkwood Commons [Member] Kirkwood Commons [Member] Klahanie Shopping Center [Member] Klahanie Shopping Center [Member] Klahanie Shopping Center [Member] Kroger New Albany Center [Member] Kroger New Albany Center [Member] Kroger New Albany Center [Member] Lake Pine Plaza [Member] Lake Pine Plaza [Member] Lake Pine Plaza [Member] Lebanon Center [Member] Lebanon Center [Member] Lebanon Center [Member] Littleton Square [Member] Littleton Square [Member] Littleton Swuare [Member] Lloyd King Center [Member] Lloyd King Center [Member] Lloyd King Center [Member] Loehmanns Plaza California [Member] Loehmanns Plaza California [Member] Loehmanns Plaza California [Member] Lower Nazareth Commons [Member] Lower Nazareth Commons [Member] Lower Nazareth Commons [Member] Market at Colonnade Center [Member] Market at Colonnade Center [Member] Market at Colonnade Center [Member] Market at Preston Forest [Member] Market at Preston Forest [Member] Market at Preston Forest [Member] Market at Round Rock [Member] Market at Round Rock [Member] Market at Round Rock [Member] Market Common Clarendon [Member] Market Common Clarendon [Member] Market Common Clarendon [Member] Marketplace Shopping Center [Member] Marketplace Shopping Center [Member] Marketplace Shopping Center [Member] Marketplace at Briargate [Member] Marketplace at Briargate [Member] Marketplace at Briargate [Member] Millhopper Shopping Center [Member] Millhopper Shopping Center [Member] Millhopper Shopping Center [Member] Mockingbird Common [Member] Mockingbird Common [Member] Mockingbird Common [Member] Monument Jackson Creek [Member] Monument Jackson Creek [Member] Monument Jackson Creek [Member] Morningside Plaza [Member] Morningside Plaza [Member] Morningside Plaza [Member] Murrayhill Marketplace [Member] Murrayhill Marketplace [Member] Murrayhill Marketplace [Member] Naples Walk [Member] Naples Walk [Member] Naples Walk [Member] Newberry Square [Member] Newberry Square [Member] Newberry Square [Member] Newland Center [Member] Newland Center [Member] Newland Center [Member] Nocatee Town Center [Member] Nocatee Town Center [Member] Nocatee Town Center [Member] North Hills [Member] North Hills [Member] North Hills [Member] Northgate Marketplace [Member] Northgate Marketplace [Member] Northgate Marketplace [Member] Northgate Plaza (Maxtown Road) [Member] Northgate Plaza (Maxtown Road) [Member] Northgate Plaza (Maxtown Road) [Member] Northgate Square [Member] Northgate Square [Member] Northgate Square [Member] Northlake Village [Member] Northlake Village [Member] Northlake Village [Member] Oak Shade Town Center [Member] Oak Shade Town Center [Member] Oak Shade Town Center [Member] Oakbrook Plaza [Member] Oakbrook Plaza [Member] Oakbrook Plaza [Member] Oakleaf Commons [Member] Oakleaf Commons [Member] Oakleaf Commons [Member] Ocala Corners [Member] Ocala Corners [Member] Ocala Corners [Member] Old St Augustine Plaza [Member] Old St Augustine Plaza [Member] Old St Augustine Plaza [Member] Paces Ferry Plaza [Member] Paces Ferry Plaza [Member] Paces Ferry Plaza [Member] Panther Creek [Member] Panther Creek [Member] Panther Creek [Member] Peartree Village [Member] Peartree Village [Member] Peartree Village [Member] Persimmon Place [Member] Persimmon Place [Member] Persimmon Place [Member] Pike Creek [Member] Pike Creek [Member] Pike Creek [Member] Pine Lake Village [Member] Pine Lake Village [Member] Pine Lake Village [Member] Pine Tree Plaza [Member] Pine Tree Plaza [Member] Pine Tree Plaza [Member] Plaza Hermosa [Member] Plaza Hermosa [Member] Plaza Hermosa [Member] Powell Street Plaza [Member] Powell Street Plaza [Member] Powell Street Plaza [Member] Powers Ferry Square [Member] Powers Ferry Square [Member] Powers Ferry Square [Member] Powers Ferry Village [Member] Powers Ferry Village [Member] Powers Ferry Village [Member] Prairie City Crossing [Member] Prairie City Crossing [Member] Prairie City Crossing [Member] Prestonbrook [Member] Prestonbrook [Member] Prestonbrook [Member] Preston Park [Member] Preston Park [Member] Preston Park [Member] Red Bank [Member] Red Bank [Member] Red Bank [Member] Regency Commons [Member] Regency Commons [Member] Regency Commons [Member] Regency Square [Member] Regency Square [Member] Regency Square [Member] Rona Plaza [Member] Rona Plaza [Member] Rona Plaza [Member] San Leandro Plaza [Member] San Leandro Plaza [Member] San Leandro Plaza [Member] Sandy Springs [Member] Sandy Springs [Member] Sandy Springs [Member] Saugus [Member] Saugus [Member] Saugus [Member] Sequoia Station [Member] Sequoia Station [Member] Sequoia Station [Member] Sherwood Market Center [Member] Sherwood Market Center [Member] Sherwood Market Center [Member] Shoppes @ 104 [Member] Shoppes @ 104 [Member] Shoppes @ 104 [Member] Shoppes of Grande Oak [Member] Shoppes of Grande Oak [Member] Shoppes of Grande Oak [Member] Shops at Arizona [Member] Shops at Arizona [Member] Shops at Arizona [Member] Shops at County Center [Member] Shops at County Center [Member] Shops at County Center [Member] Shops at Erwin Mill [Member] Shops at Erwin Mill [Member] Shops at Erwin Mill [Member] Shops at Johns Creek [Member] Shops at Johns Creek [Member] Shops at Johns Creek [Member] Shops at Mira Vista [Member] Shops at Mira Vista [Member] Shops at Mira Vista [Member] Shops at Quail Creek [Member] Shops at Quail Creek [Member] Shops at Quail Creek [Member] Shops on Main [Member] Shops on Main [Member] Shops on Main [Member] South Bay Village [Member] South Bay Village [Member] South Bay Village [Member] Southcenter [Member] Southcenter [Member] Southcenter [Member] Southpark at Cinco Ranch [Member] Southpark at Cinco Ranch [Member] Southpark at Cinco Ranch [Member] SouthPoint Crossing [Member] SouthPoint Crossing [Member] SouthPoint Crossing [Member] Starke [Member] Starke [Member] Starke [Member] Sterling Ridge [Member] Sterling Ridge [Member] Sterling Ridge [Member] Stonewall [Member] Stonewall [Member] Stonewall [Member] Strawflower Village [Member] Strawflower Village [Member] Strawflower Village [Member] Stroh Ranch [Member] Stroh Ranch [Member] Stroh Ranch [Member] Suncoast Crossing [Member] Suncoast Crossing [Member] Suncoast Crossing [Member] Tanasbourne Market [Member] Tanasbourne Market [Member] Tanasbourne Market [Member] Tassajara Crossing [Member] Tassajara Crossing [Member] Tassajara Crossing [Member] Tech Ridge [Member] Tech Ridge [Member] Tech Ridge [Member] The Hub Hillcrest Market [Member] The Hub Hillcrest Market [Member] The Hub Hillcrest Market [Member] Town Square [Member] Town Square [Member] Town Square [Member] Twin City Plaza [Member] Twin City Plaza [Member] Twin City Plaza [Member] Twin Peaks [Member] Twin Peaks [Member] Twin Peaks [Member] University Commons [Member] University Commons [Member] University Commons [Member] Valencia Crossroads [Member] Valencia Crossroads [Member] Valencia Crossroads [Member] Village at La Floresta [Member] Village at La Floresta [Member] Village at La Floresta [Member] Village at Lee Airpark [Member] Village at Lee Airpark [Member] Village at Lee Airpark [Member] Village Center [Member] Village Center [Member] Village Center [Member] Walker Center [Member] Walker Center [Member] Walker Center [Member] Welleby Plaza [Member] Welleby Plaza [Member] Welleby Plaza [Member] Wellington Town Square [Member] Wellington Town Square [Member] Wellington Town Square [Member] West Park Plaza [Member] West Park Plaza [Member] West Park Plaza [Member] Westchase [Member] Westchase [Member] Westchase [Member] Westchester Plaza [Member] Westchester Commons [Member] Westchster Commons [Member] Westchester Plaza [Member] Westchester Plaza [Member] Westchester Plaza [Member] Westlake Plaza and Center [Member] Westlake Plaza and Center [Member] Westlake Plaza and Center [Member] Westwood Village [Member] Westwood Village [Member] Westwood Village [Member] Willow Festival [Member] Willow Festival [Member] Willow Festival [Member] Woodcroft Shopping Center [Member] Woodcroft Shopping Center [Member] Woodcroft Shopping Center [Member] Woodman Van Nuys [Member] Woodman Van Nuys [Member] Woodman Van Nuys [Member] Woodmen Plaza [Member] Woodmen Plaza [Member] Woodmen Plaza [Member] Properties in Development [Member] Properties in Development [Member] Properties in Development [Member] Russell Ridge [Member] Russell Ridge [Member] Russell Ridge [Member] Sammamish-Highlands [Member] Sammamish-Highlands [Member] Sammamish-Highlands [Member] Woodside Central [Member] Woodside Central [Member] Woodside Central [Member] Corporately Held Assets [Member] Corporately Held Assets [Member] Corporately Held Assets [Member] Land Held for Future Development [Member] Land Held for Future Development [Member] Land Held for Future Development [Member] Real Estate and Accumulated Depreciation [Line Items] SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] Property, Plant and Equipment, Useful Life Property, Plant and Equipment, Useful Life Award vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Initial Cost SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost [Abstract] Land SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land Building & Improvements SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements Costs Capitalized Subsequent to Acquisition SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs Total Cost SEC Schedule III, Real Estate, Gross [Abstract] Land SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land Building & Improvements SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements Total SEC Schedule III, Real Estate, Gross Accumulated Depreciation SEC Schedule III, Real Estate Accumulated Depreciation Total Cost, Net of Accumulated Depreciation SEC Schedule III, Real Estate Investment Property, Net SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances Aggregate cost for Federal income tax purposes SEC Schedule III, Real Estate, Federal Income Tax Basis Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] Beginning balance Acquired properties SEC Schedule III, Real Estate, Other Acquisitions Developments and improvements SEC Schedule III, Real Estate, Improvements Sale of properties SEC Schedule III, Real Estate, Cost of Real Estate Sold SEC Schedule III, Real Estate, Write-down or Reserve, Amount SEC Schedule III, Real Estate, Write-down or Reserve, Amount Ending balance Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] SEC Schedule III, Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] Beginning balance Depreciation expense SEC Schedule III, Real Estate Accumulated Depreciation, Depreciation Expense Sale of properties SEC Schedule III, Real Estate Accumulated Depreciation, Real Estate Sold Provision for impairment SEC Schedule III, Real Estate Accumulated Depreciation, Other Deductions Ending balance Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Finite-Lived Intangible Liabilities [Axis] Finite-Lived Intangible Liabilities [Axis] Finite-Lived Intangible Liabilities [Axis] Finite-Lived Intangible Liabilities [Domain] Finite-Lived Intangible Liabilities [Domain] [Domain] for Finite-Lived Intangible Liabilities [Axis] Off-Market Lease, Unfavorable [Member] Off-Market Lease, Unfavorable [Member] Off-Market Lease, Unfavorable [Member] Finite-Lived Intangible Assets by Major Class [Axis] Off-Market Favorable Lease [Member] Off-Market Favorable Lease [Member] Operating Segments [Member] Operating Segments [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Gain on sale of real estate investments [Member] Gain on sale of real estate investments [Member] Gain on sale of real estate investments [Member] Equity Method Investee, Name [Axis] Investment, Name [Axis] Equity Method Investee, Name [Domain] Investment, Name [Domain] Columbia Regency Partners II, LLC [Member] Columbia Regency Partners II, LLC [Member] Columbia Regency Partners II, LLC [Member] GRI - Regency, LLC [Member] Gri - Regency, Llc [Member] Gri - Regency, Llc [Member] Other Investments in Real Estate Partnerships [Member] Other Investments in Real Estate Partnerships [Member] Other Investments in Real Estate Partnerships [Member] RegCal, LLC [Member] RegCal, LLC [Member] RegCal, LLC [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Applewood Village [Member] Applewood Village [Member] Applewood Village [Member] Garden City [Member] Plaza Venezia [Member] Plaza Venezia [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Proceeds from sale of real estate investments Proceeds from Sale of Real Estate Held-for-investment Gain on sale of real estate Equity Method Investment, Summarized Financial Information, Gain Loss on Sale of Real Estate Equity Method Investment, Summarized Financial Information, Gain Loss on Sale of Real Estate Equity in income of investments in real estate partnerships (note 4) Income (Loss) from Equity Method Investments Business Acquisition, Effective Date of Acquisition Business Acquisition, Effective Date of Acquisition Business Acquisition, Name of Acquired Entity Business Acquisition, Name of Acquired Entity Business Acquisition Location, City and State Business Acquisition Location, City and State Business Acquisition Location, City and State Business Acquisition, Description of Acquired Entity Business Acquisition, Description of Acquired Entity Business Acquisition, Co-investment Partner Business Acquisition, Co-investment Partner Business Acquisition, Co-investment Partner Equity Method Investment, Ownership Percentage Equity Method Investment, Ownership Percentage Mortgage loans assumed for the acquisition of real estate Noncash or Part Noncash Acquisition, Debt Assumed Acquired Finite-lived Intangible Asset, Amount Finite-lived Intangible Assets Acquired Acquired Finite Lived Intangible Liability Amount Acquired Finite Lived Intangible Liability, Amount Acquired Finite Lived Intangible Liability, Amount Payments to Acquire Businesses, Gross Payments to Acquire Businesses, Gross Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Investments in real estate partnerships (note 4) Preferred Stock, Dividend Rate, Percentage Preferred Stock, Dividend Rate, Percentage Number of Real Estate Properties Sold Number of Real Estate Properties Sold Number of Real Estate Properties Sold During the period. Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Notes Payable, Other Payables [Member] Notes Payable, Other Payables [Member] Receivable Type [Axis] Receivable [Domain] Notes Receivable [Member] Notes Receivable [Member] Eligible Item or Group for Fair Value Option [Axis] Eligible Item or Group for Fair Value Option [Axis] Fair Value, Option, Eligible Item or Group [Domain] Fair Value, Option, Eligible Item or Group [Domain] Notes Payable to Banks [Member] Notes Payable to Banks [Member] Unsecured Credit Facilities [Member] unsecured credit facilities [Member] unsecured credit facilities [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Derivative Liability Derivative Liability Notes Payable Notes Payable Fair Value Assumptions, Risk Free Interest Rate Fair Value Assumptions, Risk Free Interest Rate Notes Receivable, Fair Value Notes Receivable, Fair Value Disclosure Notes Payable, Fair Value Notes Payable, Fair Value Disclosure Debt Instrument, Fair Value Disclosure Debt Instrument, Fair Value Disclosure Unsecured Debt Unsecured Debt Schedule of Tax Status of Dividends [Table Text Block] Schedule of Tax Status of Dividends [Table Text Block] Schedule of Tax Status of Dividends [Table Text Block] Schedule of Preferred Stock [Table Text Block] Schedule of Preferred Stock [Table Text Block] [Table Text Block] for Schedule of Preferred Stock [Table] Schedule of Market Equity Distributions [Table Text Block] Schedule of Market Equity Distributions [Table Text Block] Schedule of Market Equity Distributions [Table Text Block] Schedule of Capital Units [Table Text Block] Schedule of Capital Units [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets Line of Credit [Member] Line of Credit [Member] Term Loan - Unsecured [Member] Term Loan - Unsecured [Member] Term Loan - Unsecured [Member] Construction Loans [Member] Construction Loans [Member] Line of Credit Facility - Unsecured [Member] Line of Credit Facility - Unsecured [Member] Unsecured Credit Line [Member] Debt Instrument, Interest Rate Terms Debt Instrument, Interest Rate Terms Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Line of Credit Facility, Unsecured, Interest Rate Description Line of Credit Facility, Interest Rate Description Line of Credit Facility, Unsecured, Annual Facility Fee Line of Credit Facility, Annual Fee Description Line of Credit Facility, Annual Fee Description Line of Credit Facility, Commitment Fee Percentage Line of Credit Facility, Commitment Fee Percentage Earnings per Share and Unit [Abstract] Earnings Per Share and Unit [Abstract] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Continuing operations Continuing Operations [Member] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Numerator [Abstract] Numerator [Abstract] Numerator [Abstract] Less: preferred stock dividends Net income attributable to noncontrolling interests Net income (loss) attributable to common stockholders Net (loss) income attributable to common unit holders Net (loss) income for common stockholders - diluted Net Income (Loss) Available to Common Stockholders, Diluted Denominator [Abstract] Denominator [Abstract] Denominator [Abstract] Weighted average common shares/units outstanding for basic EPS/EPU Weighted Average Number of Shares Outstanding, Basic Weighted average common shares/units outstanding for diluted EPS/EPU Weighted Average Number of Shares Outstanding, Diluted Income per common share - basic (note 13): Earnings Per Share, Basic [Abstract] Continuing operations (in dollars per share) Discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Net income attributable to common stockholders (in dollars per share) Earnings Per Share, Basic Income per common share - diluted (note 13): Earnings Per Share, Diluted [Abstract] Continuing operations (in dollars per share) Discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Net income (loss) attributable to common stockholders (in dollars per share) Earnings Per Common Unit, Basic [Abstract] Earnings Per Common Unit, Basic [Abstract] Earnings Per Common Unit, Basic [Abstract] Continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Per Outstanding Limited Partnership Unit, Basic, Net of Tax Discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations, Net of Tax, Per Outstanding Limited Partnership Unit, Basic Net income attributable to common unit holders (in dollars per share) Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax Earnings Per Common Unit - Diluted [Abstract] Earnings Per Common Unit - Diluted [Abstract] Earnings Per Common Unit - Diluted [Abstract] Continuing operations (in dollars per share) Income (Loss) from Continuing Operations, Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Discontinued operations (in dollars per share) Income (Loss) from Discontinued Operations, Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Net Income (Loss), Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Net Income (Loss), Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Income from continuing operations Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Statement of Comprehensive Income [Abstract] Net income Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Reclassification adjustment of derivative instruments included in net income Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Other comprehensive income (loss) Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Less: comprehensive income (loss) attributable to noncontrolling interests: Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest [Abstract] Comprehensive income attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive income attributable to the Company Comprehensive Income (Loss), Net of Tax, Attributable to Parent Statement of Cash Flows [Abstract] Capitalized interest Interest Paid, Capitalized Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Restricted Stock [Member] Restricted Stock [Member] Time Based Awards Granted Time Based Awards Granted [Member] Time Based Awards Granted [Member] Performance Based Awards Granted Performance Based Awards Granted [Member] Performance Based Awards Granted [Member] Market Based Awards Granted Market Based Awards Granted [Member] Market Based Awards Granted [Member] Common Stock [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Allocated Share-based Compensation Expense Allocated Share-based Compensation Expense Noninterest Expense Directors Fees Noninterest Expense Directors Fees Less: Amount capitalized Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount Total Stock-Based Compensation Share-based Compensation Number of shares authorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Stock Options, Outstanding, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Stock Options, Exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Stock Options, Outstanding, Ending Balance Stock Options, Vested and Expected to Vest Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Stock Options, Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Stock Options, Outstanding, Weighted Average Exercise Price, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Stock Options, Outstanding, Weighted Average Exercise Price, Ending Balance Stock Options, Vested and Expected to Vest, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Stock Options, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Stock Options, Outstanding, Weighted Average Remaining Contractual Term in Years. Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Stock Options, Vested and Expected to Vest, Weighted Average Remaining Contractual Term in Years Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Stock Options, Exercisable, Weighted Average Remaining Contractual Term in Years Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Stock Options, Outstanding, Aggregate Intrinsic Value, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Stock Options, Outstanding, Aggregate Intrinsic Value, Ending Balance Stock Options, Vested and Expected to Vest, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Stock Options, Exercisable, Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Restricted Stock, Non-Vested, Shares Outstanding, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Restricted Stock, Shares Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted Stock, Shares Vested and Distributed Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Restricted Stock, Shares Forfeited Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Restricted Stock, Non-Vested, Shares Outstanding, Ending Balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Restricted Stock, Non-Vested, Intrinsic Value Non-Vested Restricted Stock Intrinsic Value Non-Vested Restricted Stock Intrinsic Value Restricted Stock, Shares Granted, Weighted Average Grant Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Restricted Stock, Shares Vested and Distributed, Weighted Average Grant Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Restricted Stock, Shares Forfeited, Weighted Average Grant Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Restricted Stock, Shares Granted, Total Weighted Average Grant Price Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Restricted Stock, Non-Vested, Unrecognized Compensation Cost Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Number of shares available for grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Awards granted, lives Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Period for recognition for compensation costs Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Consolidated Real Estate and Accumulated Depreciation SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Text Block] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table] Property, Plant and Equipment by Type [Axis] Tenant Improvements [Member] Tenant Improvements [Member] Tenant Improvements [Member] Furniture and Fixtures [Member] Furniture and Fixtures [Member] Wholly Owned Properties [Member] Wholly Owned Properties [Member] Partially Owned Properties [Member] Partially Owned Properties [Member] Consolidated Properties [Member] Consolidated Properties [Member] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] Prior Period Reclassification Adjustment Prior Period Reclassification Adjustment Receivable with Imputed Interest, Effective Yield (Interest Rate) Receivable with Imputed Interest, Effective Yield (Interest Rate) Equity Method Investment, Accretion Period Equity Method Investment, Accretion Period Equity Method Investment, Accretion Period Operations Commenced Date Operations Commenced Date Guarantor Obligations, Percent of Secured Debt Guaranteed by Parent Guarantor Obligations, Percent of Secured Debt Guaranteed by Parent Guarantor Obligations, Percent of Secured Debt Guaranteed by Parent Parent Company, Ownership Percentage of Outstanding Common Partnership Units of Operating Partnership Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest Number of Real Estate Properties Number of Real Estate Properties General Partners' Capital Account, Units Outstanding Partners' Capital Account, Units Partners' Capital Account, Units Number Of Joint Ventures That Grant Each Partner A Right To Dissolve The Real Estate Partnership Maximum Period Of TIme In Which Company Capitalizes Interest Costs Maximum Period Of TIme In Which Company Capitalizes Interest Costs Maximum Period Of TIme In Which Company Capitalizes Interest Costs Restricted Cash and Cash Equivalents Restricted Cash and Cash Equivalents Tax Basis of Investments, Unrealized Appreciation (Depreciation), Net Tax Basis of Investments, Unrealized Appreciation (Depreciation), Net Acquired Lease Intangible Intangible Assets Disclosure [Text Block] Compensation and Retirement Disclosure [Abstract] Schedule of Deferred Compensation Arrangement with Individual, Postretirement Benefits [Table] Schedule of Deferred Compensation Arrangement with Individual, Postretirement Benefits [Table] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Axis] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Axis] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain] Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] Deferred Compensation Arrangement with Individual Disclosure, Postretirement Benefits [Table Text Block] Deferred Compensation Arrangement with Individual Disclosure, Postretirement Benefits [Table Text Block] Proceeds from sale of real estate investments Equity Method Investment, Net Sales Proceeds Revenues and expenses for the investments in real estate partnerships on a combined basis Equity Method Investment, Summarized Financial Information, Income Statement [Abstract] Total revenues Equity Method Investment, Summarized Financial Information, Revenue Operating expenses: Equity Method Investment, Summarized Financial Information, Operating Expenses [Abstract] Equity Method Investment, Summarized Financial Information, Operating Expenses [Abstract] Depreciation and amortization Equity Method Investment, Summarized Financial Information, Depreciation and Amortization Equity Method Investment, Summarized Financial Information, Depreciation and Amortization Operating and maintenance Equity Method Investment, Summarized Financial Information, Operating and Maintenance Equity Method Investment, Summarized Financial Information, Operating and Maintenance General and administrative Equity Method Investment, Summarized Financial Information, General and Administrative Equity Method Investment, Summarized Financial Information, General and Administrative Real estate taxes Equity Method Investment, Summarized Financial Information, Real Estate Taxes Equity Method Investment, Summar