Variable Interest Entities - Summarized Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Net Investment in Real Estate	$ 3,255,240	$ 3,025,429
Operating Lease Right-of-Use Assets	25,205	24,877
Cash and Cash Equivalents	162,090	21,120
Restricted Cash	37,568	131,598
Deferred Rent Receivable	84,567	77,703
Prepaid Expenses and Other Assets, Net	134,983	182,831
Total Assets	3,791,938	3,518,828
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Loans Payable, Net	143,879	173,685
Accounts Payable, Accrued Expenses and Other Liabilities	120,292	114,637
Operating Lease Liabilities	22,826	22,369
Rents Received in Advance and Security Deposits	62,092	57,534
Total Liabilities and Equity/Partners' Capital	3,791,938	3,518,828
Other Real Estate Partnerships
ASSETS
Net Investment in Real Estate	245,396	240,847
Operating Lease Right-of-Use Assets	13,173	13,257
Cash and Cash Equivalents	4,090	4,005
Restricted Cash	0	33,289
Deferred Rent Receivable	9,219	10,365
Prepaid Expenses and Other Assets, Net	8,077	9,066
Total Assets	279,955	310,829
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Loans Payable, Net	6,292	11,009
Accounts Payable, Accrued Expenses and Other Liabilities	10,067	5,747
Operating Lease Liabilities	10,304	10,329
Rents Received in Advance and Security Deposits	4,130	5,012
Partners' Capital	249,162	278,732
Total Liabilities and Equity/Partners' Capital	$ 279,955	$ 310,829