Real Estate - Dispositions (Details) - Discontinued Operations, Disposed of by Sale ft² in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($) ft² property
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties \| property		2
Gain from sale of property	$ 90,300
Tax effect of discontinued operation	$ 380
Hearst Tower
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Square Feet \| ft²		966
Sales Price		$ 455,500
Woodcrest
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Square Feet \| ft²		386
Sales Price		$ 25,300

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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+ Details