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Derivative and Other Fair Value Instruments - Summary of Fair Value Measurements for Each Major Category of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Derivatives, Fair Value [Line Items] |  |  |  |
Fair Value Of SERP Investments | $ 126,160 | $ 151,889 |  |
Other Liabilities, Fair Value Disclosure | 126,160 | 151,889 |  |
Liabilities, Fair Value Disclosure | 127,127 |  |  |
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners | 353,342 | 463,400 | $ 432,562 | $ 379,106
Forward Starting Swaps [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Forward Starting Swaps | 967 |  |  |
Fair Value, Inputs, Level 1 [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Fair Value Of SERP Investments | 126,160 | 151,889 |  |
Other Liabilities, Fair Value Disclosure | 126,160 | 151,889 |  |
Liabilities, Fair Value Disclosure | 126,160 |  |  |
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners | 0 | 0 |  |
Fair Value, Inputs, Level 1 [Member] | Forward Starting Swaps [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Forward Starting Swaps | 0 |  |  |
Fair Value, Inputs, Level 2 [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Fair Value Of SERP Investments | 0 | 0 |  |
Other Liabilities, Fair Value Disclosure | 0 | 0 |  |
Liabilities, Fair Value Disclosure | 967 |  |  |
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners | 353,342 | 463,400 |  |
Fair Value, Inputs, Level 2 [Member] | Forward Starting Swaps [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Forward Starting Swaps | 967 |  |  |
Fair Value, Inputs, Level 3 [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Fair Value Of SERP Investments | 0 | 0 |  |
Other Liabilities, Fair Value Disclosure | 0 | 0 |  |
Liabilities, Fair Value Disclosure | 0 |  |  |
Redeemable Noncontrolling Interests - Operating Partnership/Redeemable Limited Partners | 0 | $ 0 |  |
Fair Value, Inputs, Level 3 [Member] | Forward Starting Swaps [Member] |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Forward Starting Swaps | $ 0 |  |  |

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- Definition Fair value of employee holdings other than common shares within the supplemental executive retirement plan at the balance sheet date. + References No definition available. + Details
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- Definition The greater of carrying value (book value) or fair market value of an entity's issued and outstanding stock which is not included within permanent equity in Stockholders Equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. + References No definition available. + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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