Leases (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Operating Leased Assets [Line Items]
Fixed and in-substance fixed lease income		$ 196,054	$ 204,943
Variable lease income		64,067	64,668
Uncollectible straight line rent		(2,035)	(3,902)
Uncollectible amounts billable in lease income		2,275	(4,052)
Total lease income		266,357	274,537
Uncollectible lease Income from cash basis tenants		2,300
Accounts and Notes Receivable, Net		127,455		$ 143,633
Straight-line rent receivables		87,180		86,615
Tenant Receivables [Member]
Operating Leased Assets [Line Items]
Accounts and Notes Receivable, Net		21,630		39,658
Other Receivable [Member]
Operating Leased Assets [Line Items]
Accounts and Notes Receivable, Net	[1]	18,645		$ 17,360
Lessor [Member]
Operating Leased Assets [Line Items]
Above/below market rent and tenant rent inducement amortization, net		$ 5,996	$ 12,880

[1]   ⁽¹⁾ Other receivables include construction receivables, insurance receivables, and amounts due from real estate partnerships for Management, transaction and other fee income.