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Derivative and Other Fair Value Instruments - Summary of Valuations for Each Type of Fair Value Measurement (Details) | 12 Months Ended
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Dec. 31, 2020
Employee Holdings Within The Supplemental Executive Retirement Plan |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Fair Value Measurement Type | Employee holdings (other than Common Shares) within the supplemental executive retirement plan (the “SERP”)
Valuation Inputs | Quoted market prices for identical assets. These holdings are included in other assets and other liabilities on the consolidated balance sheets.
Redeemable Noncontrolling Interests Operating Partnership Redeemable Limited Partners |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Fair Value Measurement Type | Redeemable Noncontrolling Interests – Operating Partnership/Redeemable Limited Partners
Valuation Inputs | Quoted market price of Common Shares.
Mortgage Notes Payable And Private Unsecured Debt |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Fair Value Measurement Type | Mortgage notes payable and private unsecured debt (including its commercial paper and line of credit, if applicable)
Valuation Inputs | Indicative rates provided by lenders of similar loans.
Public Unsecured Notes |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |
Fair Value Measurement Type | Public unsecured notes
Valuation Inputs | Quoted market prices for each underlying issuance.

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