Fair Value Measurements - Summary of Carrying Amounts and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes and mortgages payable	$ 3,831,864	$ 3,819,434
Total liabilities	3,831,864	3,819,434
Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Notes and mortgages payable	3,879,042	3,871,644
Total liabilities	$ 3,879,042	$ 3,871,644