CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Real estate accumulated depreciation	$ 107,587	$ 91,715
Deferred costs	$ 6,872	$ 6,646
Preferred shares, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred shares, authorized (in shares)	2,000,000	2,000,000
Preferred shares, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	300,000,000	300,000,000
Common stock, outstanding (in shares)	15,172,000	15,038,000
Mortgages payable
Debt Instrument [Line Items]
Deferred costs	$ 6,448	$ 6,289
Junior subordinated notes
Debt Instrument [Line Items]
Deferred costs	347	357
Credit Facility, Maturing 2021 | Valley National Bank, Affiliate | Revolving Credit Facility
Debt Instrument [Line Items]
Deferred costs	$ 77	$ 0