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Debt Instrument, Covenant, Required Leased Property Percentage

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Debt Instrument, Floor Interest Rate

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Line Of Credit Facility, Accordion Feature, Maximum Borrowing Capacity

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Line Of Credit Facility, Duration Of Extension Option

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Line Of Credit Facility, Extension Fee Percentage

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Line Of Credit Facility, Number Of Extension Options

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Long-Term Debt, Increase (Decease)

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Percentage of Payments Of Loan Advances

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Gross amount of debt extinguished.

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Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from borrowings to finance the cost of construction.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Indebtedness - Additional Information (Details)																	4 Months Ended	12 Months Ended
Indebtedness - Additional Information (Details)	Feb. 01, 2022	Dec. 21, 2021 USD ($)	Sep. 30, 2021 USD ($)	Aug. 24, 2021 USD ($)	May 05, 2021 USD ($) extension	Apr. 15, 2021 USD ($)	Mar. 08, 2021 USD ($)	Jan. 28, 2021 USD ($)	Jan. 15, 2021 USD ($)	Dec. 22, 2020 USD ($)	Oct. 30, 2020 USD ($)	Oct. 01, 2020 USD ($)	Sep. 22, 2020 USD ($)	Aug. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Oct. 03, 2019 USD ($) extension	Feb. 01, 2022	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Feb. 18, 2022 USD ($)	Jan. 04, 2022 USD ($)	Jan. 07, 2021 USD ($)	Oct. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Indebtedness, net																		$ 917,556,000	$ 963,845,000
Total principal balances																		$ 957,387,000	$ 962,812,000
Harbor Point Parcel 3 Partnership
Debt Instrument [Line Items]
Outstanding letters of credit																						$ 15,000,000
Harbor Point Parcel 3 Partnership \| Subsequent Event
Debt Instrument [Line Items]
Outstanding letters of credit																					$ 15,000,000
Thames Street Wharf
Debt Instrument [Line Items]
Indebtedness, net			$ 71,000,000
Stated interest rate			2.35%
Southgate Square
Debt Instrument [Line Items]
Floor interest rate		0.0020
Extinguishment of debt						$ 19,500,000
Debt, face value		$ 27,100,000
Johns Hopkins Village
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																			1.25%
Lexington Square
Debt Instrument [Line Items]
Stated interest rate																		4.50%
North Point Center
Debt Instrument [Line Items]
Stated interest rate																		7.25%
Liberty Apartments
Debt Instrument [Line Items]
Stated interest rate																		5.66%
Nexton Square
Debt Instrument [Line Items]
Indebtedness, net								$ 20,100,000
Repayment of debt								$ 2,000,000
Floor interest rate								0.0025
Acquisition, assumption of debt													$ 22,900,000
Edison Apartments
Debt Instrument [Line Items]
Stated interest rate																		5.30%
The Residences at Annapolis Junction
Debt Instrument [Line Items]
Senior notes											$ 83,400,000												$ 84,400,000
Summit Place
Debt Instrument [Line Items]
Repayment of debt										$ 11,500,000
Floor interest rate										0.0040
Debt, face value										$ 23,100,000
Hoffler Place
Debt Instrument [Line Items]
Repayment of debt										$ 12,800,000
Floor interest rate										0.0040
Debt, face value										$ 18,400,000
4525 Main Street and Encore Apartments
Debt Instrument [Line Items]
Increase (decrease) in long term debt									$ 1,500,000
Indebtedness, net									$ 57,000,000
Stated interest rate									2.93%
Greenbrier Square
Debt Instrument [Line Items]
Stated interest rate				3.74%														3.74%
Acquisition, assumption of debt				$ 20,000,000
LIBOR \| Chronicle Mill
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate					3.00%
LIBOR \| Southgate Square
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate		1.90%																1.90%
LIBOR \| Market at Mill Creek
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		1.55%
LIBOR \| Nexton Square
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate								2.25%					2.25%					2.25%
LIBOR \| Summit Place
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate										2.60%
LIBOR \| Hoffler Place
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate										2.60%
LIBOR \| Wills Wharf
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		2.25%
SOFR \| The Residences at Annapolis Junction
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate											2.66%							2.66%
Bloomberg Short-Term Bank Yield \| Thames Street Wharf
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate			1.30%
New Credit Facility \| Harbor Point Parcel 3 Partnership
Debt Instrument [Line Items]
Outstanding letters of credit																						$ 15,000,000
Unsecured Debt
Debt Instrument [Line Items]
Total principal balances																		$ 210,000,000	$ 215,000,000
Construction Loans
Debt Instrument [Line Items]
Borrowings under construction loans																		23,400,000	39,700,000
Construction Loans \| Chronicle Mill
Debt Instrument [Line Items]
Number of extension options \| extension					2
Duration of extension option					12 months
Indebtedness, net					$ 35,100,000
Construction Loans \| LIBOR \| Chronicle Mill
Debt Instrument [Line Items]
Floor interest rate					0.0025
Secured Debt
Debt Instrument [Line Items]
Total principal balances																		747,387,000	747,812,000
Secured Debt \| Thames Street Wharf
Debt Instrument [Line Items]
Total principal balances																		70,761,000	70,000,000
Secured Debt \| Southgate Square
Debt Instrument [Line Items]
Total principal balances																		27,060,000	19,682,000
Secured Debt \| Market at Mill Creek
Debt Instrument [Line Items]
Total principal balances																		13,142,000	13,789,000
Secured Debt \| Johns Hopkins Village
Debt Instrument [Line Items]
Total principal balances																		0	50,859,000
Secured Debt \| Lexington Square
Debt Instrument [Line Items]
Total principal balances																		14,172,000	14,440,000
Secured Debt \| North Point Center
Debt Instrument [Line Items]
Total principal balances																		1,942,000	2,094,000
Secured Debt \| Liberty Apartments
Debt Instrument [Line Items]
Total principal balances																		13,572,000	13,877,000
Secured Debt \| Nexton Square
Debt Instrument [Line Items]
Total principal balances																		20,107,000	22,909,000
Secured Debt \| Edison Apartments
Debt Instrument [Line Items]
Total principal balances																		15,926,000	16,272,000
Secured Debt \| The Residences at Annapolis Junction
Debt Instrument [Line Items]
Total principal balances																		84,375,000	84,375,000
Secured Debt \| Wills Wharf
Debt Instrument [Line Items]
Total principal balances																		64,288,000	59,044,000
Secured Debt \| Wills Wharf \| Subsequent Event
Debt Instrument [Line Items]
Actual amount of property leased (in percent)	70.00%
Secured Debt \| Delray Beach Plaza
Debt Instrument [Line Items]
Indebtedness, net							$ 14,500,000
Secured Debt \| Greenbrier Square
Debt Instrument [Line Items]
Total principal balances																		$ 20,000,000	0
Secured Debt \| LIBOR \| Delray Beach Plaza
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate							3.00%
Secured Debt \| Minimum \| Wills Wharf \| Subsequent Event
Debt Instrument [Line Items]
Required amount of property leased (in percent)																	75.00%
Senior unsecured revolving credit facility
Debt Instrument [Line Items]
Debt effective rate																		1.70%
Senior unsecured revolving credit facility \| Minimum
Debt Instrument [Line Items]
Unused commitment fee																		0.15%
Senior unsecured revolving credit facility \| Minimum \| LIBOR
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		1.30%
Senior unsecured revolving credit facility \| Maximum
Debt Instrument [Line Items]
Unused commitment fee																		0.25%
Senior unsecured revolving credit facility \| Maximum \| LIBOR
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		1.85%
Senior unsecured revolving credit facility \| Unsecured Debt
Debt Instrument [Line Items]
Total principal balances																		$ 5,000,000	10,000,000
Senior unsecured revolving credit facility \| Unsecured Debt \| Subsequent Event
Debt Instrument [Line Items]
Total principal balances																				$ 58,000,000
Senior Unsecured Term Loan Facility
Debt Instrument [Line Items]
Debt effective rate																		1.65%
Senior Unsecured Term Loan Facility \| Minimum \| LIBOR
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		1.25%
Senior Unsecured Term Loan Facility \| Maximum \| LIBOR
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate																		1.80%
Operating Partnership
Debt Instrument [Line Items]
Outstanding letters of credit																		$ 9,500,000	$ 9,500,000					$ 9,500,000
Operating Partnership \| New Credit Facility
Debt Instrument [Line Items]
Aggregate capacity under the credit facility																$ 355,000,000
Accordion feature maximum borrowing capacity																$ 700,000,000
Number of extension options \| extension																2
Duration of extension option																6 months
Extension fee percentage																0.075%
Operating Partnership \| Senior unsecured revolving credit facility \| New Credit Facility
Debt Instrument [Line Items]
Aggregate capacity under the credit facility																$ 150,000,000
Operating Partnership \| Senior Unsecured Term Loan Facility \| New Credit Facility
Debt Instrument [Line Items]
Aggregate capacity under the credit facility																$ 205,000,000
Gainesville Development, LLC \| LIBOR
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate														3.00%
Gainesville Development, LLC \| Construction Loans
Debt Instrument [Line Items]
Aggregate capacity under the credit facility														$ 31,400,000
Floor interest rate														0.0075
Percentage of payments of loan advances														55.00%
1405 Point
Debt Instrument [Line Items]
Acquisition, assumption of debt															$ 6,100,000
Interest acquired															21.00%
Remaining lease term															42 years
Edison Apartments \| Richmond, Virginia
Debt Instrument [Line Items]
Acquisition, assumption of debt												$ 16,400,000