Fair Value Measurements (Narrative) (Details)	Jun. 30, 2022 USD ($) property	Dec. 31, 2021 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of fixed rate mortgage loans payable	$ 146,400,000	$ 159,000,000.0
Carrying value of fixed rate mortgage payable	$ 156,400,000	156,800,000
Number of properties \| property	17
Real estate held for sale	$ 719,312,000	$ 757,037,000
Level 2 [Member] \| Assets [Member] \| Retail Properties [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of properties \| property	36
Real estate held for sale	$ 719,300,000

Amount classified as assets attributable to disposal group held for sale or disposed of.

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