Credit Facilities (Summary of Credit Facilities) (Details)	3 Months Ended
	Mar. 31, 2022 property	Mar. 31, 2022	Mar. 31, 2022 USD ($)	Mar. 31, 2022 encumbered_property	Dec. 31, 2021 USD ($)
Line of Credit Facility [Line Items]
Number of properties	198			113
Outstanding balance			$ 501,988,000		$ 502,051,000
Effective interest rate		3.06%			3.00%
Credit Facility
Line of Credit Facility [Line Items]
Outstanding balance			147,333,000		$ 147,006,000
Credit Facility | Fannie Mae Master Credit Facilities
Line of Credit Facility [Line Items]
Number of properties | property	21
Outstanding balance			354,655,000		355,045,000
Credit Facility | Fannie Mae Master Credit Facilities | Capital One Facility
Line of Credit Facility [Line Items]
Number of properties | property	11
Outstanding balance			212,266,000		$ 212,417,000
Effective interest rate		2.66%			2.51%
Debt instrument, collateral amount			345,400,000
Credit Facility | Fannie Mae Master Credit Facilities | KeyBank Facility
Line of Credit Facility [Line Items]
Number of properties | property	10
Outstanding balance			142,389,000		$ 142,628,000
Effective interest rate		2.70%			2.56%
Debt instrument, collateral amount			254,500,000
Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Number of properties | property	92
Outstanding balance			0		$ 0
Effective interest rate		0.00%			0.00%
Debt, percentage bearing fixed interest, amount			50,000,000		$ 50,000,000
Term Loan | Credit Facility
Line of Credit Facility [Line Items]
Outstanding balance			150,000,000		150,000,000
Deferred financing costs			(2,667,000)		(2,994,000)
Outstanding balance, net			$ 147,333,000		$ 147,006,000
Effective interest rate		3.98%			4.11%
Term Loan | Revolving Credit Facility
Line of Credit Facility [Line Items]
Maturity extension	1 year