Variable Interest Entities - Summarized Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Assets:
Net Investment in Real Estate	$ 3,447,388	$ 3,255,240
Operating Lease Right-of-Use Assets	24,851	25,205
Cash and Cash Equivalents	55,574	162,090
Deferred Rent Receivable	93,663	84,567
Prepaid Expenses and Other Assets, Net	147,912	134,983
Total Assets	3,863,828	3,791,938
Liabilities and Partners' Capital:
Mortgage Loans Payable, Net	83,742	143,879
Accounts Payable, Accrued Expenses and Other Liabilities	119,943	120,292
Operating Lease Liabilities	22,509	22,826
Rents Received in Advance and Security Deposits	77,297	62,092
Total Liabilities and Equity/Partners' Capital	3,863,828	3,791,938
Other Real Estate Partnerships
Assets:
Net Investment in Real Estate	259,093	245,396
Operating Lease Right-of-Use Assets	13,130	13,173
Cash and Cash Equivalents	3,634	4,090
Deferred Rent Receivable	10,527	9,219
Prepaid Expenses and Other Assets, Net	9,266	8,077
Total Assets	295,650	279,955
Liabilities and Partners' Capital:
Mortgage Loans Payable, Net	2,487	6,292
Accounts Payable, Accrued Expenses and Other Liabilities	9,527	10,067
Operating Lease Liabilities	10,291	10,304
Rents Received in Advance and Security Deposits	3,730	4,130
Partners' Capital	269,615	249,162
Total Liabilities and Equity/Partners' Capital	$ 295,650	$ 279,955