CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Properties held-for-sale, accumulated depreciation	$ 1,058	$ 0
Mortgage loans receivable, loan loss reserve	2,219	2,315
Notes receivable, net of loan loss reserve	166	166
Straight-line rent receivable, allowance for doubtful accounts	$ 1,013	$ 960
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares issued	39,564,000	39,221,000
Common stock, shares outstanding	39,564,000	39,221,000
Senior Unsecured Notes
Debt issue costs, net	$ 1,235	$ 1,009