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Noncontrolling Interests (Property Partnerships) (Narrative) (Details) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Apr. 01, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Noncontrolling Interest [Line Items] |  |  |  |
Noncontrolling Interest in Limited Partnerships |  | $ 1,726,933 | $ 1,728,689 |
Payments to Noncontrolling Interests |  | $ 58,811 | 69,913 | $ 82,501
Acquisition of noncontrolling interest in property partnership |  |  | $ (186,963) |
Salesforce Tower |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners | 5.00% |  |  |
Payments to Noncontrolling Interests | $ 210,900 |  |  |
Repayment of Preferred Equity | 24,100 |  |  |
Net Payments To Minority Shareholder | 186,800 |  |  |
Acquisition of noncontrolling interest in property partnership | $ 162,500 |  |  |

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- Definition Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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