Basis of Presentation and Significant Accounting Policies (Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
Minimum percentage of taxable income distributed as dividends	90.00%
Percentage of taxable income distributed	100.00%
Deferred tax assets, net	$ 8,582	$ 15,017
Deferred tax liabilities	40,591	29,348
Income tax (benefit) expense	$ (10,496)	$ 36,630	$ 103,439
Effective income tax reconciliation, percent	(5.30%)	(8.60%)	3.00%
Net basis difference of assets and liabilities between tax basis and GAAP basis	$ 2,600,000
Estimated taxable income net	$ 413,026	$ 419,812	$ 917,162
Ordinary Income
Income Tax Contingency [Line Items]
Percentage of taxable income distributed	84.20%		62.10%
Long Term Capital Gain
Income Tax Contingency [Line Items]
Percentage of taxable income distributed			37.90%
Qualified Dividend
Income Tax Contingency [Line Items]
Percentage of taxable income distributed	15.80%
Taxable Reit Subsidiaries
Income Tax Contingency [Line Items]
Income tax (benefit) expense	$ (27,910)
Farley Office and Retail Building
Income Tax Contingency [Line Items]
Income tax (benefit) expense	10,868
220 Central Park South
Income Tax Contingency [Line Items]
Income tax (benefit) expense	$ 5,711	$ 49,221	$ 101,828