Debt - Unsecured Notes Payable - Additional Information (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022	Jul. 29, 2022	Apr. 06, 2022
Debt Instrument [Line Items]
Long-term debt outstanding	[1],[2]	$ 1,832,269	$ 1,805,414
Maximum borrowing capacity		900,000
Letters of credit, outstanding amount		7,000	7,000
Fund IV
Debt Instrument [Line Items]
Long-term debt outstanding		39,200	39,200
Mortgages | Fund Portfolio
Debt Instrument [Line Items]
Long-term debt outstanding		460,316	426,224
Mortgages | Fund Portfolio | Fund II
Debt Instrument [Line Items]
Long-term debt outstanding		137,485	133,655
Mortgages | Fund Portfolio | Fund IV
Debt Instrument [Line Items]
Long-term debt outstanding	[3],[4]	146,575	146,230
$175 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		175,000	175,000		$ 175,000
Remaining borrowing capacity		175,000
$400 Million Term Loan | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		400,000
$400 Million Term Loan | Unsecured Debt | Core Portfolio
Debt Instrument [Line Items]
Long-term debt outstanding		400,000	400,000
Subscription Line | Unsecured Debt | Fund V
Debt Instrument [Line Items]
Maximum borrowing capacity		100,000
Subscription Line | Unsecured Debt | Fund V | Letter of Credit
Debt Instrument [Line Items]
Letters of credit, outstanding amount		7,000	7,000
Subscription Line | Unsecured Debt | Fund Portfolio | Fund V
Debt Instrument [Line Items]
Long-term debt outstanding		20,266	51,210
Remaining borrowing capacity		72,700	41,800
$75 million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 75,000	$ 75,000	$ 75,000
Remaining borrowing capacity				$ 75,000

[1] Includes $1,250.8 million and $1,264.0 million, respectively, of variable-rate debt that has been fixed with interest rate swap agreements as of the periods presented. The effective fixed rates ranged from 1.14% to 4.54%.

[2] Includes $154.1 million and $103.8 million, respectively, of variable-rate debt that is subject to interest cap agreements as of the periods presented. The effective fixed rates ranged from 3.0% to 5.50%.

[3] Includes $19.3 million of a non-recourse loan in default related to 146 Geary Street, that matured with no further extension options.

[4] Includes the outstanding balance on the Fund IV secured bridge facility of $39.2 million at each of September 30, 2023 and December 31, 2022.