Notes Payable, Bank Credit Facility, Interest Expense and Amortization of Deferred Debt Costs - Additional Information (Detail)											12 Months Ended
	Dec. 18, 2024 USD ($)	Sep. 24, 2024 USD ($)	May 28, 2024 USD ($)	Mar. 08, 2023 USD ($)	Sep. 06, 2022 USD ($)	Aug. 24, 2022 USD ($)	Aug. 04, 2022 USD ($)	Jun. 07, 2022 USD ($)	Mar. 11, 2022 USD ($)	Nov. 19, 2021 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 01, 2030	Oct. 01, 2027	Jun. 30, 2023 USD ($)	Aug. 23, 2022 USD ($) swap	Feb. 23, 2022 USD ($)
Debt Instrument [Line Items]
Outstanding debt											$ 1,550,000,000
Related debt											1,047,832,000	$ 935,451,000
Variable rate debt											186,489,000	274,715,000
Long-term debt repayments of principal and balloon payments											$ 1,552,688,000	1,410,000,000
Debt outstanding with fixed-rate												1,130,000,000
Debt outstanding with variable-rate												276,000,000.0
Interest rate spread on LIBOR											0.10%
Term loan facility payable, net											$ 99,679,000	99,530,000
Number of interest rate swaps | swap																	2
Construction loans payable, net											198,616,000	77,305,000
Repayments of secured debt											105,593,000	42,332,000	$ 174,096,000
Loss on early extinguishment of debt											0	0	648,000
Remaining loan balance											455,786,000
Unamortized deferred debt costs											20,072,000	19,300,000
Accumulated amortization											11,200,000	10,600,000
Capitalization of debt issuance cost											$ 3,500,000	400,000	$ 9,900,000
Revolving Credit Facility
Debt Instrument [Line Items]
Interest rate spread on LIBOR											1.40%
Term Facility
Debt Instrument [Line Items]
Interest rate spread on LIBOR											1.35%
Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Available borrowing capacity											$ 134,500,000
Term loan facility payable, net											287,000,000
Letter of Credit
Debt Instrument [Line Items]
Term loan facility payable, net											185,000
Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity											525,000,000.0
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity											425,000,000.0
Line of Credit | Term Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity											100,000,000.0
Mortgages
Debt Instrument [Line Items]
Repayments of debt				$ 9,300,000
Mortgage Notes Payable
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure												2,000,000
Fixed rate mortgage notes payable
Debt Instrument [Line Items]
Related debt											1,370,000,000	1,130,000,000
Variable rate loans payable
Debt Instrument [Line Items]
Variable rate debt											187,000,000.0
Term Loan | Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity																	$ 100,000,000
Term Loan | Secured Debt | Agreement Ending October 1, 2030
Debt Instrument [Line Items]
Derivative, notional amount																	50,000,000
Term Loan | Secured Debt | Agreement Ending October 1, 2030 | Scenario, Forecast
Debt Instrument [Line Items]
Derivative, fixed interest rate														2.91%
Term Loan | Secured Debt | Agreement Ending October 1, 2027
Debt Instrument [Line Items]
Derivative, notional amount																	$ 50,000,000
Term Loan | Secured Debt | Agreement Ending October 1, 2027 | Scenario, Forecast
Debt Instrument [Line Items]
Derivative, fixed interest rate															2.96%
BJ’s Wholesale Club | Mortgages
Debt Instrument [Line Items]
Long-term debt, term				10 years
Loan amount				$ 15,300,000
Loan fixed interest rate				6.07%
Loan required periodic principal and interest payment				$ 99,200
Amortization schedule				25 years
Debt instrument, payment at maturity				$ 11,700,000
Twinbrook Quarter
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure											$ 129,600,000
Guarantor obligations, liquidation proceeds, percentage											100.00%
Twinbrook Quarter | 3.80% Fixed Rate Loan Maturing In 2035
Debt Instrument [Line Items]
Loan amount										$ 145,000,000
Amortization schedule										25 years
Twinbrook Quarter | 3.83% Fixed Rate Loan Maturing In 2041
Debt Instrument [Line Items]
Loan fixed interest rate										3.83%
Construction-to-Permanent Loan | Secured Debt
Debt Instrument [Line Items]
Loan amount											$ 71,400,000							$ 133,000,000
Loan fixed interest rate																		3.90%
Amortization schedule											25 years
Construction-to-Permanent Loan | Construction Loans
Debt Instrument [Line Items]
Construction loans payable, net																$ 127,300,000
Lansdowne Town Center Mortgage | Mortgages
Debt Instrument [Line Items]
Repayments of secured debt									$ 28,300,000
Orchard Park Mortgage | Mortgages
Debt Instrument [Line Items]
Repayments of secured debt								$ 8,600,000
Village Center Loan | Mortgages
Debt Instrument [Line Items]
Long-term debt, term							15 years
Loan amount							$ 25,300,000
Loan fixed interest rate							4.14%
Loan required periodic principal and interest payment							$ 135,200
Amortization schedule							25 years
Debt instrument, payment at maturity							$ 13,400,000
Repayments of debt							11,200,000
Loss on early extinguishment of debt							$ 400,000
Great Falls Center Loan | Mortgages
Debt Instrument [Line Items]
Long-term debt, term						7 years
Loan amount						$ 31,500,000
Loan fixed interest rate						3.91%
Loan required periodic principal and interest payment						$ 164,700
Amortization schedule						25 years
Debt instrument, payment at maturity						$ 25,700,000
Repayments of debt						8,000,000
Loss on early extinguishment of debt						$ 200,000
Beacon Center and Seven Corners Loan | Mortgages
Debt Instrument [Line Items]
Long-term debt, term					15 years
Loan amount					$ 143,000,000
Loan fixed interest rate					5.05%
Loan required periodic principal and interest payment					$ 840,100
Amortization schedule					25 years
Debt instrument, payment at maturity					$ 79,900,000
Repayments of debt					85,300,000
Debt instrument, prepayment penalty					$ 5,900,000
Kentlands Square I
Debt Instrument [Line Items]
Remaining loan balance											$ 26,500,000
Hampden House
Debt Instrument [Line Items]
Guarantor obligations, maximum exposure											$ 74,000,000
Guarantor obligations, liquidation proceeds, percentage											100.00%
Guarantor obligations, current carrying value											$ 26,600,000
Debt Covenant
Debt Instrument [Line Items]
Notes payable to bank											$ 1,600,000,000	$ 1,500,000,000
Credit agreement leverage ratio											60.00%
Interest coverage ratio required minimum											2
Required fixed charge coverage ratio											1.4
Avenel Business Park, Leesburg Pike Plaza Center, and White Oak Shopping Center | Mortgages
Debt Instrument [Line Items]
Long-term debt, term			13 years 4 months 24 days
Loan amount			$ 100,000,000
Loan fixed interest rate			6.38%
Loan required periodic principal and interest payment			$ 686,300
Amortization schedule			23 years 4 months 24 days
Debt instrument, payment at maturity			$ 61,500,000
Repayments of debt			$ 51,200,000
Thruway Shopping Center | Mortgages
Debt Instrument [Line Items]
Long-term debt, term		15 years
Loan amount		$ 70,000,000
Loan fixed interest rate		6.41%
Loan required periodic principal and interest payment		$ 468,700
Debt instrument, payment at maturity		$ 41,700,000
Ashburn Village Shopping Center | Mortgages
Debt Instrument [Line Items]
Long-term debt, term	15 years
Loan amount	$ 50,000,000
Loan fixed interest rate	5.47%
Loan required periodic principal and interest payment	$ 306,100
Amortization schedule	25 years
Debt instrument, payment at maturity	$ 28,400,000
Repayments of debt	$ 20,500,000
Thruway Mortgage
Debt Instrument [Line Items]
Remaining loan balance											$ 17,500,000
Long-term debt, gross											$ 69,800,000